dont override cid

The `cid` was bugging me because things that extend `ampersand-state` (like `ampersand-view`) were always having their `cid` set to `stateN` instead of `viewN`. Is it safe to assume that if an instance already has a cid property that it should not be overwritten?

Also a few other cleanup changes:
- update precommit-hook
- use browserify, tape-run and tap-spec to run tests