[TASK] Upgade CKEDITOR to 4.7.1

CKEditor have realeased a new version, containing fixes
primarily for table selection, but also some general
fixes.

Mexican spanish have also been added as a supported
language.

Changes:
 * Added a new Mexican Spanish localization
 * Added Paste as Plain Text keyboard shortcut to the
 Accessibility Help instructions.
 * [Chrome] Fixed: Mouse actions on CKEditor scrollbar
 throw an exception when the Table Selection plugin is loaded.
 * Fixed: Selection started from a nested table causes
 an error in the browser while scrolling down.
 * [Firefox] Fixed: Enter key breaks the table structure
 when pressed in a table selection.
 * Fixed: Error thrown when deleting content from the
 editor with no selection.
 * [Chrome] Fixed: Error thrown by the Enter Key plugin
 when pressing Enter with no selection.
 * Fixed: Error thrown by Tab Key Handling and Indent
 List plugins when pressing Tab with no selection in inline editor.
 * Fixed: Anchors inserted with the Link plugin on collapsed
 selection cannot be edited.
 * Fixed: The Table Resize plugin throws an error when used
 with a table with only header or footer rows.
 * Fixed: The editor.getCommandKeystroke method does not
 obtain the correct keystroke.
 * [IE] Fixed: Paste from Word does not work in Quirks Mode.
 * Fixed: CKEDITOR.filter incorrectly transforms the margin
 CSS property.

Release blog post:
http://ckeditor.com/blog/CKEditor-4.7.1-released
Release notes:
http://ckeditor.com/release-notes

Resolves: #81752
Releases: master, 8.7

Change-Id: I75b7b8d134c01c6541144e462402e733ce8e1dab
Reviewed-on: https://review.typo3.org/53362


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>
Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: Benni Mack <benni@typo3.org>