core: Upgrade all templates to Bootstrap 3.0.0

Squashed commit of the following:

commit dddb811a853d47cb302b6be3cec94080467a3721
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Tue Sep 30 14:54:47 2014 +0200

    mod_admin_frontend: Fix editor initialization in tabs

commit a2e7e3a31e97b43f6006828a17f66a38acf6dcc2
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Tue Sep 30 14:54:03 2014 +0200

    mod_admin: Fix editor initialization in tabs

commit 3c452ae8dcf5c6433d9f075c6f4cf4d61f178114
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Mon Sep 1 17:39:18 2014 +0200

    Fix TinyMCE media plugin

commit 4a08bbcf8bf3b377be463da1b9e9551eed6b0953
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Mon Sep 1 14:54:59 2014 +0200

    Some more CSS tweaks to make the widgets less heavy

commit 3e73bddbd3adf4c470d518da0deb469f00c249fd
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Mon Sep 1 14:41:09 2014 +0200

    Add latest admin bootstrap CSS from github

    https://github.com/zotonic/bootstrap/tree/zotonic-admin-bs3

commit 50646275bc2458677b1c5ee07ee6f092c459a802
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Mon Sep 1 12:05:37 2014 +0200

    gradients in widget header

commit 2c26bf068d39e7c900742f25f10589921e120efc
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Mon Sep 1 11:12:21 2014 +0200

    Admin logon, tweaks

commit 832e5dc8aa70e192603e221bf28f77b8520c46a0
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Mon Sep 1 11:02:20 2014 +0200

    mod_base_site bootstrap 3

commit 2b1a0e95df0f5700424b9c50bbb0ce9ad112c46b
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Mon Sep 1 10:49:34 2014 +0200

    Fix skel, move bootstrap-3 over regular bootstrap

commit fe41b90192bfc230cc1b56e486091d338e2dd91c
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Sun Aug 31 17:04:31 2014 +0200

    Start on skel bootstrap fixes

commit fac091d56602b11ba2a071a2825bd8f2c6be996d
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Sun Aug 31 15:02:40 2014 +0200

    Bootstrap3 zotonic_status site

commit 88a4b5c726e2e927f08b758b0ce50898b2c5e398
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Sun Aug 31 14:50:46 2014 +0200

    Navbar CSS

commit 3671c4d21227bb253d18278a1833df88afb42432
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Sun Aug 31 14:29:14 2014 +0200

    Work on editing blocks, i18n

commit d906fde721448199874fb3e4fb797b50c82c34a4
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Sun Aug 31 14:00:28 2014 +0200

    Misc fixes

commit 6dfaaa6367a3bed01a00b1c506accb092acce4e2
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Sun Aug 31 13:21:11 2014 +0200

    More forms in dialogs fixed

commit a4abb5f20cf111da6c3e6b4484dcdcf87102d1f8
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Fri Aug 29 18:42:23 2014 +0200

    More work on admin pages

commit 16782b5b93c77fd413a46eaede2fbc1575b15e9d
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Fri Aug 29 14:13:18 2014 +0200

    WIP on template checks for all modules

commit e0fa1af0fdd41b0769315cd97d0d1c28a5885ddb
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Fri Aug 29 10:54:35 2014 +0200

    Admin edit page tweaks, dialog

commit 659490a26db15c351ff4636893c798ff1d561f8e
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Fri Aug 29 10:36:22 2014 +0200

    Move admin CSS into LESS file; work on styling; fix admin widgets

commit 16b0d191cc31fb1131f325dd64385fdd4bf88453
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Thu Aug 28 23:01:52 2014 +0200

    WIP

commit 9fbfb6251fc2dfd92532f33770f0e673cc9bc9bc
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Thu Aug 28 22:56:22 2014 +0200

    Manual work

commit 812eda8a11d6e6b0c1e86e6cceebc6b46a3f56d4
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Thu Aug 28 22:37:29 2014 +0200

    Fixes, upgrade tool dba1246

commit c61ed741b5317abfe54da83b21b3049ff831a3b2
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Thu Aug 28 22:21:24 2014 +0200

    Convert template files to bootstrap 3 using conversion tool

    https://github.com/arjan/bootstrap3-upgrader/blob/8c03b889d8c90093e4c4180b83940d1930f366d2/upgrade.py

commit a41ae4f3a288a3250746c4a93c9d22d7e039f36d
Author: Arjan Scherpenisse <arjan@scherpenisse.net>
Date:   Wed Aug 27 21:34:20 2014 +0200

    Add initial version of Bootstrap 3