Added StringMaker (for partially specialising string conversions), extended BDD macros and moved file/line info to top of message.
Re-enable ANSI colour by default - hopefully properly excluding Windows this time
Patched issue where an assert before the first section can cause a set-fault (needs a better fix, though)
Build 21

Merge commit '767f1588dc208ef6b22b83e18e645786770ce204' into merge-up-int

Conflicts:
	include/internal/catch_tostring.hpp
	single_include/catch.hpp
Merge commit '90b2bfec3ddd89dd8b5ae550c3edfc05b23ba0f3' into merge-up-int

Conflicts:
	single_include/catch.hpp