Add in < and == operators to JobMeshRequirments and test them.

We want to be able to support storing JobMeshRequirements in stl containers
and using algorithms on those containers, so we need to add in < and ==
operators.

Change-Id: I3155bb17f68323d9a406fb63ed557d2ac2235e56
Add in the ability to create md5 hashes in remus.

This is needed to efficiently compare JobContents and JobSubmissions to
each other, as parsing the large binary blobs multiple times will not
be efficient.

Change-Id: Ibfb5d5fcfd7270e6e0c205bcde73a10ea3d60f54
Make JobContent store a MD5Hash of the data for faster comparisons.

Change-Id: I6502b12c9d4cd8f0b64322280eff049dce2a0a8b
Correct some compiler warnings.

Change-Id: I997b5d5eeb305c6ca21a28e2735e3fa636991813