Build: Switch to JSHint RC file

- Based off of jQuery recommendation except double quotemark
- The ant task also doesn't support the "globals" property in the JSON
file
Linting: Trim trailing space
Linting: cleanup unused variable warnings
Linting: Enforce onevar option
Linting; Remove pe and jQuery globals

Replaced with jquery JSHint option and the "browser" option for the
theme references to window.
"pe" global only kept for the themes and polyfill where they don't use
the "_pe" cached version
Build: Add jshintignore for CLI based linting
Merge pull request #2957 from nschonni/jshint-dotfiles

Linting