Fix functions names - according to libalpm API changes

[paluh]

Caution: I'm not Lisp programmer!

I've updated functions names and implemeted simple accessor for alpm_list->data as alpm_list_getdata was removed from libalpm (I'm afraid especially about correctness of this piece).

[paluh]

I think that there is a bug in my pull request - supported libalpm versions list should be changed from:

(:unix (:or "libalpm.so.8" "libalpm.so.7" "libalpm.so.6" "libalpm.so.5" "libalpm.so.3" "libalpm.so"))

to

(:unix (:or "libalpm.so.8" "libalpm.so"))

Should I introduce such a change?

[skypher]

Thanks! I will take care of integrating this properly and put out a new release soon.