Started 4.4.6 development.
API Docs: minor correction in filter.js.
API Docs: Shared Space plugin.
Tests: Removing and restoring filling char on image creation.
Store the anchor offset so it can be precisely restored when restoring the filling char.
Tests: Tests for #8617 and #12491.
Store anchor and focus nodes, because they may be changed when chaning filling node's text.
Extracted repeating fragments of tests.
Tests: Added test for keeping selection direction when removing filling char.
Keep selection's direction when removing filling char.
Tests: Test for preserving selection's direction when taking snapshot.
Preserve selection's direction when taking snapshot.
Changelog entry.
Merge branch 't/12491'
Fixed HTML comparisons failing when using Bender jobs, which are run with special URLs that contain upper case letters.
JSCS and JSHint fixes in filter tests.
Allow dashes in element names in the string format of allowed content rules.
Changelog entry.
Merge branch 't/12501'
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