Specify full path to worker for worker [run|deregister|list]

[srossross]

@PeterDSteinberg Lets improve on #165. Can you add the ability to specify the exact worker:

e.g.

anaconda worker run @sean/test-q/osx-1

Running a worker without the full path should raise a deprication warning.

anaconda worker run osx-1

[PeterDSteinberg]

@srossross I will do this. That's a relatively quick change.

[PeterDSteinberg]

@srossross are we waiting to merge #165 until this issue #177 ? That makes sense to me.

[PeterDSteinberg]

@srossross there is already a check in place for existing worker --name usage. Here's an example:

$ anaconda worker register psteinberg/abc -n ps_abc1
Using Anaconda Cloud api site http://api.anaconda.org
[BinstarError] Cannot have duplicate worker --name from same host: ps_abc1

It doesn't look like there is any ambiguity. The changes in this issue would not be backwards compatible to our VM's documentation. Are you sure we should change?

[stephenakearns]

Recommendation: go thru next deployment smoothly and then make this interface change (which can cause instability. also needs to address backwards compatability