Add support for transpiling ES6 Unicode regular expressions

https://github.com/mathiasbynens/regexpu
https://mathiasbynens.be/notes/es6-unicode-regex
Use HTTPS for the demo REPL

GitHub Pages offers HTTPS out-of-the box — there’s no reason not to use it.
Use the `files` directive in `package.json` instead of `.npmignore`

`.npmignore` is a blacklist, while `files` is a whitelist-based approach. The latter is much easier to maintain. See https://www.npmjs.org/doc/files/package.json.html#files for more info.

This patch does not affect the files that are included in the package.
Delete `codereview.settings`

It’s not needed anymore ever since Traceur moved to GitHub.
Fix issue with finally in async functions

We were not correctly going to the finally state after an await
when there were no more statement (including generated) after the
await in the try block.

This sets the finallyFallThrough state and updates the callback id
to go the finally state.

Fixes #1316
Simplify compiler code path and add support for sourceRoot.

The sourcemap sourceRoot is a common prefix like a baseURL for the
the filenames in a sourcemap. It allows the map to be more compact by
reducing the number of repeated strings.

Sorting out how to set this was hampered by the compile chain complexity
at the "write" end of the chain. Reducing functions and callbacks makes
things clearer.

Fixes #1324 and fixes #1310

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/1325

Closes #1325, closes #1324, closes #1310.
0.0.61
Redirect old Google Code demo URL to new HTTPS URL
Pass filenames as arguments, not via options.

Fixes #1326

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/1331

Closes #1331, closes #1326.
instantiate generators fix
ModuleEvaluationError with stack.

Strip frames from the root cause stack.

Fixes #1329

Review URL: https://api.github.com/repos/google/traceur-compiler/issues/1336

Closes #1336, closes #1329.
Remove out of date todo
Recompute `entries_.length` on every iteration.
Most recent ES6 spec says that on every `next` call of MapIterator the number of elements in entries should be recomputed. See 23.1.5.2.1 10
I'm less sure about `Map.prototype.forEach` but unlike Array.prototype.forEach the spec doesn't specify that `len` should be cached. See 23.1.3.5
0.0.62