Added several new features

The commit to 1.9.1.0-git-nightly contains following changes:
- New design
- Several security fixes
- Support for copying and moving files
- Support for moving directories (copying will follow at the next build)
- Register from web interface
- Program config
- Share module
- Account contingent
- New icon set
- Getting size informations of files and directories
- Added a /Documents/ Folder for a small documentation (large will
follow)
- Database errors are indexied by 0xx to get a better debugging purpose
- This commit is still unstable. Use with caution