Initial commit of quotients starting from a file from @SkySkimmer.
Adding Quotients
Adding Global Instances
Removing dead code
Cleaning up quotients
Merge pull request #193 from spitters/master

Adding Quotients
Prove Admitted theorems in types.ObjectClassifier

They are not very pretty, but they are no longer admits.  This is
partial work on #195.
Add a theorem with issig equivalence about hProps
Merge pull request #197 from JasonGross/hProp-theorem

Add a theorem with issig equivalence about hProps
Merge pull request #196 from JasonGross/remove-admitted-objclassifier

Prove Admitted theorems in types.ObjectClassifier
Merge branch 'master' of https://github.com/HoTT/HoTT
removed redundant quotient.v