But do it during the build process for cjs.
Right now we only need this when we transpile from ts
directly to es5. This is only the case in our
cis build, as for our browser build we only transpile
from ts to es6 via ts and then use traceur to do
the rest.
This removes .es6 files which are pure duplicates of a
.ts file in the same folder.
Next we need to remove .js files as well, and remove karma preprocessors for dart.
This is a prerequisite for switching to TypeScript. We need to remove the Traceur preprocessor
from Karma, so we have the build specified in a single place (broccoli tree def'n).
Adds a gulp task which builds the .ts files (in the cjs build only).
The new files have extension .ts since they are now valid typescript.
Unfortunately until Typescript can emit System.require, we have to keep the old .es6 version
so traceur works inside the Karma preprocessor. This should be fixed soon.
