We depend on glob >4.3, correct package.json

See also issue #1542

TBR=@arv

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/1547

Closes #1547.
Stop chdir into test for feature tests.

Fixes #1317
Remove require() calls in Loader test.
Fixes #1546

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/1548

Closes #1548, closes #1317, closes #1546.
Move regexpu to devDependencies, as it is not required in deps.
Block binding: Fix issue with sibling scopes

This introduces a new Scope subclass that keeps track of references.
Then we use that to determine if we need to rename the binding or not.

Fixes #1358
Correct the key for sourcemaps in mode 'memory'
Add unit test for sourceMaps:memory from interpreter
Add sourceURL when the input name differs from output name.
respond to review
Index the sourcemaps by both input and output names