[Pulp-list] Synchronizers in Pulp && File Based Syncs support

[Pradeep Kilambi]

I have file syncs working in pulp. While working on this, I 
re-architected our sync implementation in pulp to be compatible with 
generic content design. I will go through this in our deep dive as well, 
so you can choose to skip and wait for deep dive. Here is wiki for two 
documents,

Pulp Synchronizer Architecture: 
https://fedorahosted.org/pulp/wiki/PulpSynchronizer

File Based Syncs in Pulp : 
https://fedorahosted.org/pulp/wiki/FileBasedSync#PulpGrinderIntegration

I pushed the code to master. I think I covered all the areas I could 
think of and made sure all tests pass.

If you see any weirdness please ping me.

Thanks,
~ Prad