Improve user experience with software management

Currently user has to deal with a lot of technicals related with software management. He has to know what packages are, what dependencies are, he has to scroll through oversized packages list and dig into their untranslated descriptions.

This is frustrating and nonunderstandable for usual user, and should be replaced with some user friendly software management system that could separate user experience from all these technical things.

And we also should improve dpkg system. I know that this is propably the most advanced package system available on Linux but is also very limited and overcomplicated.

We should add few fearures to dpkg to make it more usable.

1. Remove unused packages (reverse dependency removal).
2. Add ability for conditional dependencies.