RPM Support

This is for Pulp 3. Since we introduced sync optimizations, the issue we had in Pulp 2 is now also relevant to Pulp 3.

Pulp uses revision numbers in repomd.xml to determine if contents need to be updated on sync. However "modifyrepo" does not generate new revision numbers for non rpm data.

Steps:
1) Setup the following repo

$ mkdir /tmp/my-data
$ cd /tmp/my-data
$ wget https://partha.fedorapeople.org/test-repos/rpm-with-productid/elephant-0.3-0.8.noarch.rpm
$ createrepo .
$ echo "100000" >> productid
$ modifyrepo  --mdtype=productid productid repodata
$ grep revision repodata/repomd.xml
  <revision>1554217257</revision>

2) Sync this repo
3) Now update the repo

$ cd /tmp/my-data
$ echo "100001" >> productid
$ modifyrepo  --mdtype=productid productid repodata
$ grep revision repodata/repomd.xml
  <revision>1554217257</revision>

Notice that the revision number did not change even though a metadata file got updated. Try resyncing this change and notice that the productid change will get ignored.