Rewrite format and parse in terms of detail::fields<Duration>

* Add format and parse to utc_time<Duration>.
* Added more tests.

tz.html

@@ -26,7 +26,7 @@
 <br/>
 <br/>
 <a href="mailto:howard.hinnant@gmail.com">Howard E. Hinnant</a><br/>
-2017-01-28<br/>
+2017-02-25<br/>
 </address>
 <hr/>
 <h1 align=center>Time Zone Database Parser</h1>
@@ -2001,8 +2001,6 @@ void
 to_stream(std::basic_ostream&lt;CharT, Traits&gt;&amp; os, const CharT* fmt,
           const std::chrono::duration&lt;Rep, Period&gt;& d);
 </pre>
-<blockquote>
-</blockquote>
 
 <pre>
 template &lt;class CharT, class Traits, class Duration&gt;
@@ -2010,8 +2008,6 @@ void
 to_stream(std::basic_ostream&lt;CharT, Traits&gt;&amp; os, const CharT* fmt,
           const local_time&lt;Duration&gt;&amp; tp);
 </pre>
-<blockquote>
-</blockquote>
 
 <pre>
 template &lt;class CharT, class Traits, class Duration&gt;
@@ -2019,8 +2015,6 @@ void
 to_stream(std::basic_ostream&lt;CharT, Traits&gt;&amp; os, const CharT* fmt,
           const sys_time&lt;Duration&gt;&amp; tp);
 </pre>
-<blockquote>
-</blockquote>
 
 <pre>
 template &lt;class CharT, class Traits, class Duration&gt;
@@ -2028,6 +2022,14 @@ void
 to_stream(std::basic_ostream&lt;CharT, Traits&gt;&amp; os, const CharT* fmt,
           const zoned_time&lt;Duration&gt;&amp; tp);
 </pre>
+
+<pre>
+template &lt;class CharT, class Traits, class Duration&gt;
+void
+to_stream(std::basic_ostream&lt;CharT, Traits&gt;&amp; os, const CharT* fmt,
+          const utc_time&lt;Duration&gt;&amp; tp);
+</pre>
+
 <blockquote>
 <p>
 These are lower-level functions with respect to <code>format</code>.  These functions
@@ -2071,6 +2073,15 @@ template &lt;class CharT, class Traits, class Duration&gt;
 std::basic_string&lt;class CharT, class Traits&gt;
 format(const std::basic_string&lt;class CharT, class Traits&gt;&amp; format, const sys_time&lt;Duration&gt;&amp; tp);
 
+template &lt;class CharT, class Traits, class Duration&gt;
+std::basic_string&lt;class CharT, class Traits&gt;
+format(const std::locale&amp; loc, const std::basic_string&lt;class CharT, class Traits&gt;&amp; format,
+       const utc_time&lt;Duration&gt;&amp; tp);
+
+template &lt;class CharT, class Traits, class Duration&gt;
+std::basic_string&lt;class CharT, class Traits&gt;
+format(const std::basic_string&lt;class CharT, class Traits&gt;&amp; format, const utc_time&lt;Duration&gt;&amp; tp);
+
 template &lt;class CharT, class Traits, class Rep, class Period&gt;
 std::basic_string&lt;CharT&gt;
 format(const std::basic_string&lt;CharT, Traits&gt;&amp; fmt, const std::chrono::duration&lt;Rep, Period&gt;&amp; d);
@@ -2101,6 +2112,14 @@ template &lt;class CharT, class Duration&gt;
 std::basic_string&lt;class CharT&gt;
 format(const CharT* format, const sys_time&lt;Duration&gt;&amp; tp);
 
+template &lt;class CharT, class Duration&gt;
+std::basic_string&lt;class CharT&gt;
+format(const std::locale&amp; loc, const CharT* format, const utc_time&lt;Duration&gt;&amp; tp);
+
+template &lt;class CharT, class Duration&gt;
+std::basic_string&lt;class CharT&gt;
+format(const CharT* format, const utc_time&lt;Duration&gt;&amp; tp);
+
 template &lt;class CharT, class Rep, class Period&gt;
 std::basic_string&lt;CharT&gt;
 format(const CharT* fmt, const std::chrono::duration&lt;Rep, Period&gt;&amp; d)
@@ -2254,6 +2273,30 @@ template &lt;class Duration, class CharT, class Traits&gt;
 parse(const std::basic_string&lt;CharT, Traits&gt;&amp; format, local_time&lt;Duration&gt;&amp; tp,
       std::chrono::minutes&amp; offset, std::basic_string&lt;CharT, Traits&gt;&amp; abbrev);
 
+template &lt;class Duration, class CharT, class Traits&gt;
+<i>unspecified istream manipulator</i>
+parse(const std::basic_string&lt;CharT, Traits&gt;&amp; format, utc_time&lt;Duration&gt;&amp; tp);
+
+template &lt;class Duration, class CharT, class Traits&gt;
+<i>unspecified istream manipulator</i>
+parse(const std::basic_string&lt;CharT, Traits&gt;&amp; format, utc_time&lt;Duration&gt;&amp; tp,
+      std::basic_string&lt;CharT, Traits&gt;&amp; abbrev);
+
+template &lt;class Duration, class CharT, class Traits&gt;
+<i>unspecified istream manipulator</i>
+parse(const std::basic_string&lt;CharT, Traits&gt;&amp; format, utc_time&lt;Duration&gt;&amp; tp,
+      std::chrono::minutes&amp; offset);
+
+template &lt;class Duration, class CharT, class Traits&gt;
+<i>unspecified istream manipulator</i>
+parse(const std::basic_string&lt;CharT, Traits&gt;&amp; format, utc_time&lt;Duration&gt;&amp; tp,
+      std::basic_string&lt;CharT, Traits&gt;&amp; abbrev, std::chrono::minutes&amp; offset);
+
+template &lt;class Duration, class CharT, class Traits&gt;
+<i>unspecified istream manipulator</i>
+parse(const std::basic_string&lt;CharT, Traits&gt;&amp; format, utc_time&lt;Duration&gt;&amp; tp,
+      std::chrono::minutes&amp; offset, std::basic_string&lt;CharT, Traits&gt;&amp; abbrev);
+
 template &lt;class Rep, class Period, class CharT, class Traits&gt;
 <i>unspecified istream manipulator</i>
 parse(const std::basic_string&lt;CharT, Traits&gt;&amp; format,
@@ -2307,6 +2350,29 @@ template &lt;class Duration, class CharT, class Traits&gt;
 parse(const CharT* format, local_time&lt;Duration&gt;&amp; tp, std::chrono::minutes&amp; offset,
       std::basic_string&lt;CharT, Traits&gt;&amp; abbrev);
 
+template &lt;class Duration, class CharT&gt;
+<i>unspecified istream manipulator</i>
+parse(const CharT* format, utc_time&lt;Duration&gt;&amp; tp);
+
+template &lt;class Duration, class CharT, class Traits&gt;
+<i>unspecified istream manipulator</i>
+parse(const CharT* format, utc_time&lt;Duration&gt;&amp; tp,
+      std::basic_string&lt;CharT, Traits&gt;&amp; abbrev);
+
+template &lt;class Duration, class CharT&gt;
+<i>unspecified istream manipulator</i>
+parse(const CharT* format, utc_time&lt;Duration&gt;&amp; tp, std::chrono::minutes&amp; offset);
+
+template &lt;class Duration, class CharT, class Traits&gt;
+<i>unspecified istream manipulator</i>
+parse(const CharT* format, utc_time&lt;Duration&gt;&amp; tp,
+      std::basic_string&lt;CharT, Traits&gt;&amp; abbrev, std::chrono::minutes&amp; offset);
+
+template &lt;class Duration, class CharT, class Traits&gt;
+<i>unspecified istream manipulator</i>
+parse(const CharT* format, utc_time&lt;Duration&gt;&amp; tp,
+      std::chrono::minutes&amp; offset, std::basic_string&lt;CharT, Traits&gt;&amp; abbrev);
+
 template &lt;class Rep, class Period, class CharT&gt;
 <i>unspecified istream manipulator</i>
 parse(const CharT* format, std::chrono::duration&lt;Rep, Period&gt;&amp; d);