Better Enums 0.11.3

Additions

• BETTER_ENUMS_DECLARE_STD_HASH for declaring std::hash specializations (#77, Sven Scharmentke).
• BETTER_ENUMS_CLASS_ATTRIBUTE for injecting tokens into the class declaration (#80, Michael Ernst).

Bugs fixed

• -Wold-style-cast on Clang (#74, Felipe Lema).
• Don't trigger compiler bug with -Wattributes on GCC ≥ 7 (#79, CJ Smith).
• Missing BETTER_ENUMS_IGNORE_ATTRIBUTES_* definitions on Clang (#81, Jan-Gerd Tenberge).