Enterprise install needs to be able to support keys that come from package and strings

[viglesiasce]

Right now keys cannot be installed from the Eucalyptus license rpm, they must be entered in as strings which does not map to how customers install.

[nephomaniac]

Some other considerations related to enterprise cert/keys:
-doing some of this in the euca-deploy project and syncing across machines. (to avoid a clear text representation of the license in the json, etc..
-doing some validation on the cert (such as expiration) prior to referencing them in the repo