Up the warning level, and fix the resulting warnings with msvc, gcc and Intel.

Fix bug in docs and regenerate.

[SVN r65208]

libs/regex

@@ -1 +1 @@
-Subproject commit ae013c447c81b63a120480312a349d869ab8621c
+Subproject commit f4d925ad3b3f24b575a62e2d5f4b95e733c8c293