Add a matcher that checks exception's message

Only works for exceptions that publicly derive from `std::exception`
and the matching is done exactly, including case and whitespace.

Closes #1649
Closes #1728

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include/internal/catch_capture_matchers.h

@@ -10,6 +10,7 @@
 
 #include "catch_capture.hpp"
 #include "catch_matchers.h"
+#include "catch_matchers_exception.hpp"
 #include "catch_matchers_floating.h"
 #include "catch_matchers_generic.hpp"
 #include "catch_matchers_string.h"