Revision 791140

Name view index files by their function hashes for no downtime deploys. Closes COUCHDB-218

Adds ability to switch view indexes on the fly by building the index from a "staging" design doc, and then COPYing the staging doc to the production doc's id. Since indexes are referenced by view definition, the new version of the production design doc will point immediately to the index files already built in staging.

Please use and give feedback.