Fixed app list right container to not overlap left container scrollbar

- Container widths in apps list now use pixels instead of em
- Container widths now match properly and rightcontainer doesn't overlap
  the scrollbar any more
Show (group) after groups in share dropdown
Added DAV client wrapper that support timeout values

Since SabreDAV does not support passing a timeout value to curl, this
commit adds a subclass for it that will set the timeout value to
curlRequest().
Added timeout value to WebDAV post setup check

Fixes #5357
Fix warning box in IE8

 * simulates a black transparent background on a blue pane
new option to add reshares to the result
adjust tests
add test for the reshare option
new console command to generate sql migration scripts
Fixed sharing status update for new/uploaded files

Creating new files, folders or uploading files now have their sharing
icon updated accordingly.

For this, the global share status list that is cached in
OC.Share.statuses is reused for new files.

Performance should improve as the sharing list is now only loaded once
per navigation session.

In OC.Share, split loadIcons into loadIcons + updateIcons.

Fixes #4977
Merge pull request #5385 from owncloud/generate-sql-migration-master

new console command to generate sql migration scripts
only call shell_exec if enabled
Added missing var in share.js
Merge pull request #5381 from owncloud/files-sharingstateafterupload

Fixed sharing status update for new/uploaded files
fix comment
Merge pull request #5389 from owncloud/fix_shell_exec

only call shell_exec if enabled
update 3rdparty submodule
Fixed zip download button for unlimited filesize in public mode

Added missing condition to check whenever allowed zip size is unlimited.

Fixes #3717
split up reset()['path'] to make it compatible with older PHP versions
Move OC_Connector_Sabre_Server to expected location.