Add one line to fix an edge case in Safari

Situation:
When body tag has 'user-select:none', paste with Ctrl+V doesn't work in Safari

See [this CodePen for demo](http://codepen.io/getshao/pen/fwmuy)

Notice how copy and paste with Ctrl + C / Ctrl + V works in all browsers except Safari
Targeted fix to Safari only.
Changelog entry.
Merge branch 't/12506'
Fix a typo
Enhanced and completed the plugin definition docs.
Reverted mess commited in f0c7750. So ashamed.
Tests: Add test for editor inheriting the initial editable focus.
Preset the editable as currently active element in focus manager.
Changelog entry.
Merge branch 't/11647'
Docs: Plugin definition API.
Moved a private method to the end of the main closure.
Docs: config.contentsLangDirection corrected.
fix typo in the docs
Merge pull request #135 from brizzz/master

Fix typo in the docs
API docs: Mentioned that contentsCss does not work in full page mode.
Tests: Prevent crash on IE8.
Tests: Added tests for hypothetical problem described in #12546.
Tests: Removed jQuery-dependent code from the Bender.js extension.