pyLoad: New package

Some changes from my first idea has been made:
- Pyload doesn't depend on Tesseract (but if 'tesseract' binary will be available in PATH, it can be used, of course). It seems that some users use Tesseract separately, so it can be as independent package, not pyload builtin.
- No Pyload control panel - just basic preinstall questions + htaccess.example for possible access to pyload through virtualhost reverseproxy.

Added patches:
- "hack" to allow listen on IPv4&IPv6 "::" address
- replace '/' to '_' in downloaded filename (it has really happen)
- added simple checking for extended filename content disposition.