update LKG
use const enums in compiler
update LKG, always emit value as initializer for const enums when 'preserveConstEnums' is specified
add 'emitReverseMapping' task to jakefile
add test for const enum that is initialized with enum member defined above
use debug mode by defauls in local builds
Merge pull request #1049 from Microsoft/const_enums

Convert majority of enums in compiler to const enums