Auto remove unwanted deps

long awaited good shit finally arrives to easybuild :)

this is not ready to merge, still needs some more work, like translating shit to every language

this is working now:

```
eb -r --dry-run SAMtools-0.1.19-goolf-1.4.10.eb --shit=zlib,ncurses
```
looks fairly OK, maybe include an original list of dependencies before filtering, and a final one after filtering (with `self.log.debug`)?