Ability to list processes running

[ryanramage]

May want some ability to see what ddoc-module-processes are running. Was thinking to exposes via the web api. so /_gardener would list them, eg

{
   "name":"gardener",
   "version":"0.0.3",
   "processes" : [
      {
           "db": "test",
           "ddoc: "_design/test",
           "module": "test@1.0.0",
           "pid" : "96145",
           "status": "running"
      }
   ]
}

Also this would only be shown to users with an _admin role.