Split metrics/version/command out of api.clj and into their own
namespaces
(PDB-238) - Remove v1 API

This commit removes the v1 API and builds on the HTTP api refactor.
This commit contains:

- Remove all v1 namespaces and the namespaces calling them
- Remove api tests excercising the v1 routes
- Remove v1 references in the docs
Merge pull request #840 from senior/ticket/master/pdb-238-remove-v1

(PDB-238) Remove v1 API