update routine implemented
version number of files_versions increased

Conflicts:

	apps/files_versions/lib/hooks.php

- fixes oc-314
- caching of the 'big' images in subfolder view
  next to the tumbnails
- now choosen to use max 1200px for viewing
  this helps speeding up the viewing process

Signed-off-by: BlackEagle <ike.devolder@gmail.com>

fopen() didn't work for large files on some servers while readfile()
seems to work for all files on all configurations.

This reverts commit f5c329af.