Remove context abort for all REST createContext

Adding all the finally context.aborts, was one too many
All requests had aborted contexts, which errored always
Also a spelling fix
Shrink writeStats signature, DSO type constant unneccessary
Change /rest/bitstreams/:id/retrieve to @GET, post didn't make sense to me
Remove extra context.aborts in various rest helpers
Merge pull request #1 from LongsightGroup/rest-crud-cz

Quick fixes for REST Read endpoints