catch and log exception in OC_Helper::cleanTmp()

Fix dav permissions for folders

Don't keep the full info of all children in memory

Don't complain about non-writable datadirs before we're installed

Clarify possible preview providers for type Office

Disable external code coverage

a

Show a proper error message when trying to scan the filesystem for a non...

Show login again instead of JSON if CSRF check fails

user/backed: use pow of two for backed action constants

Drop only if exists

Check for blacklisted characters

fix filepicker home icon being partly hidden, fix #10169

Fixes https://github.com/owncloud/core/issues/11264

(This should in future get moved to the mountpoint class - but that is something for @icewind1991 ;-))

Do not show exception to the end-user - use a proper error page instead

Moved WebDAV check to client side JS

the current implementation limits number of possible backed actions
to 8 as it uses pow of 16 for constants. This change introduces pow
of two and allows up-to 32 actions to be defined.

The old values are preserved for backward compatibility.

Previously a JSON error page was shown to the user in-case the CSRF token was not valid. This was confusing and prevented people from login.

With this at least the login page is shown again and not a JSON error message. I consider this as sufficient since adding a new error page just for this sake would uneededly make lib/base.php even more cluttered and this is a edge-case which optimally should anyways not happen that often.

This can be tested by opening the login page, then clearing the cookies, and trying to login.

DragnDrop Upload text style

send browsers timezone back tp the server on login

Fix icon classes, disappeared delete icon

Fix share key pattern matching

Instead of inaccurate pattern matching, use the list of users who we
know have access to the file to build the list of share keys.

This covers the following cases:

- Move/copy files into a subfolder within a share
- Unsharing from a user
- Deleting files directlry / moving share keys to trashbin

Use only lower-case letters

Do only follow HTTP and HTTPS redirects

- Added setup checks in JavaScript
- Moved isWebDAVWorking to JS using SetupChecks
- Moved internet connection checks to an ajax call that goes through the
  server