Merge pull request #1631 from lavalamp/fix

Fix build error in integration test
Use etcd as backend for minion registry.
Rename InsertMinion to CreateMinion.
Rebase to master, change JSONBase to TypeMeta.
Fix the exec test, on os x false and true have different paths, but they're in $PATH on all.
Merge pull request #1632 from brendandburns/fix

Fix the exec test, on os x false and true have different paths
Merge pull request #1478 from ddysher/minion-etcd

Use etcd as backend for minion registry.
Fix malformed namespace json tag
fix error message in validation test
fix captured loop variable
Fix struct tag in apparently untested config struct
Fix mismatched arg and formatter in Errorf
fix extra un-cosmetic extraneous code.