Updates ownCloud title to Application - ownCloud

A fix for https://github.com/owncloud/core/issues/5369

- [ ] we show the username on the top right always, we should cut the username from the title as it is completely unnecessary there.
- [ ] the | pipe bar is ugly and we should use a simple - dash instead.
- [ ] gotta check various apps that @PVince81 said that change things. (News App as an example changes it to ' | ' @Raydiation @zimba12 can you check? :) )

@owncloud/designers @karlitschek