Fix youtu.be regex so it supports capital letters and properly escapes hyphens.
Use protocol-relative URLs.
Fixed so the editor renders in XHTML mode apparently some people still use this rendering mode.
Merge pull request #347 from Kindling/patch-media-regex

Fix media plugin regexes and use protocol-relative URIs.
Fixed minor issue in saucelabs.js.
Updated icons to match the latest icomoon format and enabled -moz-osx-font-smoothing on FF Mac OS X.
Added speak and variant overrides to css icons.
Allow suppression of alt and dimension fields in image plugin.
Non-negative settings requiring explicit `false` for suppressing image fields.
Allow suppression of alt source, poster, and dimensions fields.
Protect against missing alt source and poster fields.
Non-negative settings requiring explicit `false` for suppressing media fields.
Fixed bug where tabindex on elements within the editor contents would cause issues on some browsers.
Added some unit tests to the tabindex fix.
Fixed bug where link text wouldn't be properly updated in gecko if you changed an existing link.
Added new table_grid option that allows you to disable the table grid and use a dialog.
Fixed a event order bug in MenuItem.js
Merge pull request #348 from Kindling/patch-media-settings

Allow suppression of alternate source, poster, and dimension fields in media plugin.
Merge pull request #346 from Kindling/patch-image-settings

Allow suppression of alt and dimension fields in image plugin.
Updated changelog.txt.