Fixed bug#8494 - Added button and keyboard shortcut in CKEditor to split quotes.

Squashed commit of the following:

commit 2e4e5fbb5d44db91ff1d93848c208f47a5e133a2
Merge: da014f8 0ed1056
Author: Marc Nilius <marc.nilius@otrs.com>
Date:   Mon May 12 11:08:17 2014 +0200

    Merge branch 'master' into bug-8494-mn-master

commit da014f80aee560f2382e60f93e4226d60fbb620b
Author: Marc A. Bonsels <marc.bonsels@otrs.com>
Date:   Mon May 12 11:03:39 2014 +0200

    Updated images; added non-retina icon.

commit 034db711cbf42b066c7c1dda5aec3cf80cc4fea7
Author: Marc Nilius <marc.nilius@otrs.com>
Date:   Mon May 12 11:02:32 2014 +0200

    Fixed typo.

commit 4de9ecbe35a4173057c54c0d0ec1f64c97d57bab
Author: Marc Nilius <marc.nilius@otrs.com>
Date:   Mon May 12 11:01:28 2014 +0200

    Prepared plugin for HiDPI icon.

commit be6c8812b3bd40a47826d00100830263b7889300
Author: Marc A. Bonsels <marc.bonsels@otrs.com>
Date:   Thu May 8 10:17:46 2014 +0200

    Added icon for splitquote.

commit efb642760603f44dca9b588afda9eefd7b8cc52b
Author: Marc Nilius <marc.nilius@otrs.com>
Date:   Tue May 6 02:47:45 2014 +0200

    Made text in plugin translatable.

commit 8a03e72adf66db8643021479c19bcf429d3ac7e1
Author: Marc Nilius <marc.nilius@otrs.com>
Date:   Tue May 6 00:14:14 2014 +0200

    Added more functionality.

commit cae5e3378b39e54a170504c9749d77ccb9782f47
Author: Marc Nilius <marc.nilius@otrs.com>
Date:   Mon May 5 16:06:30 2014 +0200

    First step for split quote plugin.

Conflicts:

	Kernel/Output/HTML/Standard/RichTextEditor.dtl
Updated CHANGES.
Follow-up fix for bug#8494. Added 'Split Quote' button also for Custoemr Interface RTE.

Conflicts:

	Kernel/Output/HTML/Standard/CustomerRichTextEditor.dtl
Fixed issue with temporary directories creation.
Fixed issue in UT scenarios where the framework has already installed packages.
Fixed error with tmp folder creation.
Fixed error detecting the support data checks.
Removed use of cache as it could produce wrong results.
Fix merge-error
Fixed typo.
Merge branch 'rel-3_3' of github.com:peterk/otrs into rel-3_3
Added two new options to otrs.ArticleStorageSwitch.pl to improve the usage in big systems.