Move JSHint config to jshintrc files

Follows-up 3f1f88b725.

Also:
* Moved jquery.cookie.js to src/ directory to allow using a separate
  configuration for it (also complements /build, and other jQuery plugin
  repositories).
* Simplified Grunt configuration.
Merge pull request #313 from Krinkle/jshint

Move JSHint config to jshintrc files
updated main property value
Merge pull request #314 from jstrimpel/master

updated main property value
Fixing references for a couple of package managers after moving plugin into src.

See b106a0e23640281321cf7ced832f6dc8fb88a085.
Updating copyright
travis: Don't run grunt-saucelabs for pull requests

Fixes constant build failures because Travis' secure environment
variables are not (and should not) be exposed for pull requests.