copr-dist-git hotfixes

[Michal Novotny]

Hello,

there were some problems in the last release that we tackled yesterday and
today. Namely:

- wrong package version information displayed in UI
- extending Release with scm commit hash for MockSCM method (that was not
intended)
- packing sources for SCM methods did not work if repo contained a symlink
loop

These particular problems should be fixed now.
COPR team