Added nothrow docs

Command-line.md

@@ -111,4 +111,18 @@ Examples:
 <pre>
 -n testRun
 -n "tests of the widget component"
-</pre>
+</pre>
+
+
+## Eliding assertions expected to throw
+<pre>
+-nt, --nothrow
+</pre>
+
+Skips all assertions that test that an exception is thrown, e.g. REQUIRE_THROWS.
+<p>
+These can be a nuisance in certain debugging environments that may break when exceptions are thrown (while this is usually optional for handled exceptions, it can be useful to have enabled if you are trying to track down something unexpected).
+</p>
+<p>
+When running with this option the throw checking assertions are skipped so as not to contribute additional noise.
+</p>