Restructure

This restructuring is needed to provide proper python package project. Please see the diffs for changes. No functional changes should be done, only restructuring related.
You can pass any variable directly, like this:
`make install DESTDIR=/ `

On my Fedora, the command above works well. On Debian I'm able to install without any extra `DESTDIR` variable setting. Do you think we should hard-coded it (/usr)?