AMD and ES6 interop support

Under modules=amd, mark modules with property '__esModule', and treat all other modules as default exports to allow mixing ES6 and AMD modules under both ES6 and AMD loaders.

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/785

Closes #785.
Followup cleanup from last commit
Print a stack trace when the interpreter sees an exception.

Set the process.exit code to 8 on error
Fixes #812

Reviewed on #814.

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/823

Closes #823, closes #812.
Simplify the ErrorReporter to not support rest params

The usage of rest params is less useful now that we have full support for template literals.

Review URL: https://github.com/google/traceur-compiler/pull/821

Closes #821
CPS transformer: Extract the variable hoisting

Move the variable hoisting out of CPSTransformer into its own transformer. Then let the CPSTransformer hook into that for its machine generated variables.

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/817

Closes #817.
only include __moduleName if set

Currently modules with no name are having `__moduleName = (void 0);` written in.

This removes that.

It is useful because a dynamic loader can then set this `__moduleName` variable in an outer scope when evaluating the module to give it a name when loaded.

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/825

Closes #825.
Update third_party/codemirror2 to codemirror-3.22

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/805

Closes #805.
Tweak repl css
Use input file names to set __moduleName for node compiles

Fixes #813

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/827

Closes #827, closes #813.
Remove calls to getModuleImpl.

Fixes #754.
TODO: remove the function after npm update.

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/830

Closes #830, closes #754.
-v or --version prints version and exits.

Fixes #829

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/832

Closes #832, closes #829.
Rewrite ParseTreeMapWriter to generate better SourceMap entries.

We were missing the endings of trees. Fixes #766.

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/843

Closes #843, closes #766.