* fix #7484
* use UID, css, and div instead of span

There is no need to refer to the absolute path here if we can use the relative one.

Conflicts:
	lib/private/templatelayout.php

adding argument deleteSelf to rmdirr() - if false the directory itself will not be deleted only it's content

adding repair step to clean the asset cache after upgrade + coding style adjustments

This leads to the regeneration of the hash in case a single application is updated.

Fixes https://github.com/owncloud/core/issues/11374

Conflicts:
	core/templates/layout.guest.php

Step one, open guest layout for different styles.

Conflicts:
	lib/private/vcategories.php

And other small improvements

 - Use camelCase

 - Add some phpdoc

 - Fix some indents

 - Use some more spacing

revert changes to fbbc76f2 because master is very unstable right now

Without an additional name it's nearly impossible to write positive security model based rules since the parameter name isn't defined.