First cut of Grunt build

- Left the Ant build in place with a minor update to the new package.json location
- Minor linting issues fixed
- Using Node version of parser-lib for concatenation with a shim for "exports" being undefined on other platforms
- Removed concatenated test files since they can be run individually

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TODO:
- [x] Release task: copy files from build and call the git log
- ~~Re-enable and fix issues identified by using the newer version of JSHint~~ This was a difference between the Grunt defaults and JSHint defaults. Can be investigated at a later date
- [x] Use `require` to load parser-lib on Node platform #367

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Future
- Extract YUITest wrapper to standalone grunt plug-in
- Add README generator as discussed in #365
- Remove ant build once tasks have parity