Misc small fixes to suppress warnings.

Code should now be clean with msvc /W4 and gcc /Wall /Wextra -pedantic with the exception of one deliberate warning in one test.

[SVN r57510]

test/lexical_cast_abstract_test.cpp

@@ -51,7 +51,7 @@ std::ostream &operator<<(std::ostream &O, const A &a)
 {
     a.out(O);
     return O;
-};
+}
 
 void test_abstract()
 {