Add sorting to files list, trashbin and public files
Set default sort of trashbin to timestamp descending
Added unit test in files app for sort function in helper class

Added unit test for the Helper class in the files app that tests the
different sort orders.
$RUNTIME_APPTYPES is no longer used - left over from pre OC4
html input tag has no closing tag
typos, indentation and remove of unused code
Clear selection on reload (when changing sort)
Merge pull request #8041 from owncloud/files-sortcolumns

File list sorting by clicking on column headers