prevent user from creating or renaming sth. to an existing filename
- show tooltip when violating naming constraints while typing
- when target filename exists on server fallback to dialog to interrupt the users flow because something unexpected went wrong
- fixes #5062
- also fixes some whitespace and codestyle issues in files js
- uses css selector over filterAttr in touched js files
adding PHPDoc comments
fixing undefined variable $newname
fixing js syntax error
Merge branch 'master' into prevent_user_from_creating_or_renaming_to_an_existing_filename

Conflicts:
	apps/files/js/filelist.js
fix message dialog titles in IE8
use correct filename in error result json
cleanup precondition checking when creating new files / folders
- use i18n
- use trim when checking for empty file / folder name
- use more verbose error descriptions
add missing ;
cleanup array value assignment
use a more descriptive error message when the user tries to create '/Shared'
Merge branch 'master' into prevent_user_from_creating_or_renaming_to_an_existing_filename

Conflicts:
	apps/files/js/filelist.js
fix translations
Merge pull request #5477 from owncloud/prevent_user_from_creating_or_renaming_to_an_existing_filename

prevent user from creating or renaming sth. to an existing filename