Vapour: changed window._timer to use vapour.doc as cache

1. This moves the element search context one level up so that plugin
   elements in the `<head>` can also be found (e.g. mobile favicon).
2. Saves the creation of another `$( document )` jQuery object.
3. Saves the logic required to check if the window._timer _cache has been
   initialized.
Favicon: initial commit of the favicon plugin

1. Uses `<link rel="shortcut icon">` as its plugin element.
2. Default behaviour is to add a mobile favicon to the page if a
   shortcut icon is defined.
3. Also provides events to update the mobile and shortcut favicons.
Corrected mime type for svg image
Merge pull request #3165 from fbernard2/v4.0

Corrected mime type for svg image
Modified the grunt task to allow a task that doesn't run the hinting (dist)
Merge pull request #3168 from LaurentGoderre/grunt-changes

Modified the grunt task to allow a task that doesn't run the hinting (dist)
Only load the jshintrc file when needed
Fixed various jshint issues
Removed temporary SCSS Windows hacks

- Bump Magnific popup for upstream fixes and remove checked in copies
- Remove `unquote` hacks
Merge pull request #3169 from LaurentGoderre/grunt-changes

Only load the jshintrc file when needed
Merge pull request #3137 from patheard/mobile-favicon

Mobile favicon plugin
Lightbox: Ported over most of v3.1 working examples.
Sesssion: initial rough port of 3.1 plugin

Exposes plugin keepalive and inactivity checks via the
`keepalive.wb-session-timeout` and `inactivity.wb-session-timeout`
events.
Merge pull request #3166 from patheard/session-timeout

Sesssion Timeout: initial rough port of 3.1 plugin
Merge pull request #3171 from pjackson28/lightboxfixes

Lightbox: Ported over most of v3.1 working examples.
Build: Specific copy:* and task descriptions

- Task descriptions are shown running `grunt --help`
- Adds new "assets" task for other files copied to the dist
- Move test/jshint call to the high level dist/debug chains
SCSS: Extract variables to common sheet

Fixes gh-3150
SCSS: Cleanup base imports
Bower: Don't exclude dot files

Some of these are required for the theme re-builds
Merge pull request #3173 from nschonni/v4-build-cleanup

Build: Specific copy:* and task descriptions