fix pattern for database names - #629

Files: prevent people from renaming files to '.'

adding file name checks and notifications to isFileNameValid() for . and empty file name

Updater progress feedback

Remove old data directory protection from update, should already have taken place or not working because the server isn't Apache

workaround for 32-bit systems to handle filesizes bigger than 2GB

External API for ownCloud based on OCS

Only show the version updating to instead of worrying about converting internal to a formatted version

Special case of BSD has been added as stat syntax differs
In addition unknown OS is logged

And some documentation adjusted on the way

Remove echo from lost password page