Added a -h flag to the lingon command. Also added the ability for plugins to provide help messages for the tasks they define

Change-Id: I9fb3e9f8eeca37ae6f8ee8047dab56995754b25b
Merge branch 'master' into command-help
Using the liftoff package for the lingon cli
Added lingon cli binary
Merge pull request #33 from jpettersson/command-help

Created the lingon cli & added a help flag: lingon -h