RPMCALLBACK_INST_STOP added by rpm.org

rpm.org has decided to change the rpmtsCallback() by
adding another event: the addition is going to break
a lot of code because many applications implicitly
depend on a series of events arriving in *exactly*
one order (i.e. they are treating as a progress bar pushing stream,
not as events per-se).

Patch series starts here
    http://bazaar.launchpad.net/~rpm5/rpm/rpm.org/revision/11219

The compatibility issues need to bee reviewed and will have
an effect on changes to the rpm-callback-elimination blueprint