Option to remove Casper Remote one-off policies

[sheagcraig]

When running a Casper Remote task, a policy object is created. This policy does not show up in the web ui, but does remain in the object db.

I'll add a command to search for these and allow you to clean them.

[sheagcraig]

Reopened due to discussion on Slack.

from @dnikles on slack:

anything fitting the pattern ####-##-## at I’m considering casper remote and removing.

example:
<policy><id>42</id><name>2016-09-09 at 11:15 PM | jssadmin | 1 Computer</name></policy>

[aarondavidpolley]

Dupe of issue #8