Fix issue with Windows style path separators
Make sure we replace backslashes earlier
Add support for binary and octal numeric literals

This is on by default but can be turned off using
--numeric-literals=false

We support 0b11 and 0o77 in all places where NumericLiteral
is supported.
Add support for return yield expression
Merge pull request #319 from arv/return-yield

Add support for return yield expression
Merge pull request #316 from arv/numeric-literal

Add support for binary and octal numeric literals
Merge pull request #313 from arv/fix-windows-build

Fix issue with Windows style path separators
Update bin/traceur.js