[packagekit] yum2 error fixes

[Richard Hughes]

In the yum2 backend we have loads of these:

            except yum.Errors.InstallError,e:
                msgs = ';'.join(e)
                self.ErrorCode(ERROR_PACKAGE_ALREADY_INSTALLED,msgs)
                self.Exit()

i.e. in an error, send error code, and exit the script.

What we probably need to do is:

Not fatal errors (i.e. the script can continue):

   self.ErrorCode(ERROR_PACKAGE_ALREADY_INSTALLED,"foo")
   self.Finished(EXIT_FAILED)
   return

and for fatal errors:

   self.ErrorCode(ERROR_INTERNAL_ERROR,"foo")
   self.Finished(EXIT_FAILED)
   self.Exit()

I think we are exiting quite a bit without needing to - and we certainly
need to send finished else bad things happen to the daemon.

Thanks guys,

Richard.