Tidy up tests, build scripts, and documentation:

* Concepts split up into individual files
* Function definitions moved to .ipp files
* Add more tests to fill gaps in coverage
* Fix documentation Xsl

include/beast/http/write.hpp

@@ -18,13 +18,30 @@
 namespace beast {
 namespace http {
 
-/** Write a HTTP/1 message to a stream.
+/** Write a HTTP/1 message on a stream.
 
-    @param stream The stream to send the message on.
+    This function is used to write a message to a stream. The call
+    will block until one of the following conditions is true:
 
-    @param msg The message to send.
+    @li The entire message is sent.
 
-    @throws boost::system::error code on failure.
+    @li An error occurs.
+
+    This operation is implemented in terms of one or more calls
+    to the stream's `write_some` function.
+
+    The implementation will automatically perform chunk encoding if
+    the contents of the message indicate that chunk encoding is required.
+    If the semantics of the message indicate that the connection should
+    be closed after the message is sent, the error returns from this
+    function will be `boost::asio::error::eof`.
+
+    @param stream The stream to which the data is to be written.
+    The type must support the @b `SyncWriteStream` concept.
+
+    @param msg The message to write.
+
+    @throws boost::system::error Thrown on failure.
 */
 template<class SyncWriteStream,
     bool isRequest, class Body, class Headers>
@@ -32,11 +49,28 @@ void
 write(SyncWriteStream& stream,
     message_v1<isRequest, Body, Headers> const& msg);
 
-/** Write a HTTP/1 message to a stream.
+/** Write a HTTP/1 message on a stream.
 
-    @param stream The stream to send the message on.
+    This function is used to write a message to a stream. The call
+    will block until one of the following conditions is true:
 
-    @param msg The message to send.
+    @li The entire message is sent.
+
+    @li An error occurs.
+
+    This operation is implemented in terms of one or more calls
+    to the stream's `write_some` function.
+
+    The implementation will automatically perform chunk encoding if
+    the contents of the message indicate that chunk encoding is required.
+    If the semantics of the message indicate that the connection should
+    be closed after the message is sent, the error returns from this
+    function will be `boost::asio::error::eof`.
+
+    @param stream The stream to which the data is to be written.
+    The type must support the @b `SyncWriteStream` concept.
+
+    @param msg The message to write.
 
     @param ec Set to the error, if any occurred.
 */
@@ -47,13 +81,35 @@ write(SyncWriteStream& stream,
     message_v1<isRequest, Body, Headers> const& msg,
         error_code& ec);
 
-/** Start writing a HTTP/1 message to a stream asynchronously.
+/** Start an asynchronous operation to write a HTTP/1 message to a stream.
 
-    @param stream The stream to send the message on.
+    This function is used to asynchronously write a message to a stream.
+    The function call always returns immediately. The asynchronous
+    operation will continue until one of the following conditions is true:
+
+    @li The entire message is sent.
+
+    @li An error occurs.
+
+    This operation is implemented in terms of one or more calls to the
+    stream's `async_write_some` functions, and is known as a <em>composed
+    operation</em>. The program must ensure that the stream performs no
+    other write operations (such as @ref async_write, the stream's
+    `async_write_some` function, or any other composed operations that
+    perform writes) until this operation completes.
+
+    The implementation will automatically perform chunk encoding if
+    the contents of the message indicate that chunk encoding is required.
+    If the semantics of the message indicate that the connection should
+    be closed after the message is sent, the operation will complete with
+    the error set to `boost::asio::error::eof`.
+
+    @param stream The stream to which the data is to be written.
+    The type must support the @b `AsyncWriteStream` concept.
 
     @param msg The message to send.
 
-    @param token The handler to be called when the request completes.
+    @param handler The handler to be called when the request completes.
     Copies will be made of the handler as required. The equivalent
     function signature of the handler must be:
     @code void handler(
@@ -62,9 +118,9 @@ write(SyncWriteStream& stream,
     Regardless of whether the asynchronous operation completes
     immediately or not, the handler will not be invoked from within
     this function. Invocation of the handler will be performed in a
-    manner equivalent to using boost::asio::io_service::post().
+    manner equivalent to using `boost::asio::io_service::post`.
 
-    @note The message must remain valid at least until the
+    @note The message object must remain valid at least until the
           completion handler is called, no copies are made.
 */
 template<class AsyncWriteStream,
@@ -85,6 +141,9 @@ async_write(AsyncWriteStream& stream,
     The function converts the message to its HTTP/1 serialized
     representation and stores the result in the output stream.
 
+    The implementation will automatically perform chunk encoding if
+    the contents of the message indicate that chunk encoding is required.
+
     @param os The ostream to write to.
 
     @param msg The message to write.