Skarmark 1095332 1094498

This commit resolves following 2 bugs -

https://bugzilla.redhat.com/show_bug.cgi?id=1094498
https://bugzilla.redhat.com/show_bug.cgi?id=1095332

Summary of the 2 parts of the fixes -
1. Added logic in both check_repo and check_all_and_associate functions to check for the actual file on the filesystem for supported unit types before skipping the download.
2. Updated location where check_all_and_associate function is called (and also the function itself, since the input is in a different form in this case) so that the progress information takes already downloaded packages into consideration.