initial implementation of constant folding
handle non-qualified names, add 'propagateEnumConstants' command line option
added folding for references to enum members in enum member initializers, added tests
addressed CR feedback, added support for indexed access
move code around to consolidate checks in one place
dropped redundand type assertion, added mising check
merge with master
'const enum' iteration 0. TODO: allow and track const enums in imports, add more tests
merge with master
const enums, iteration 1: const enums can be used in imports, const enums can be merged only with const enums.
allow arithmetic operations in constant expressions, handle infinity\NaN results
addressed CR feedback
Adding type aliases to language specification
added .d.ts generation tests
set 'earlyError' bit to 'non-constant expression in constant enum initializer' error
Move back to how we used to walk trees for incremental parsing perf.
Merge pull request #1021 from Microsoft/incrementalPerf

Move back to how we used to walk trees for incremental parsing perf.
When augmenting Array.prototype, make the functions non-enumerable by default so as to not affect clients that call for-in
Speed up separatedListChildCount
Merge branch 'master' into defineProperty