OpenShift Express Tool: Create a way to invoke rhc-sshkey functionality which posts a newly created key-pair's public key to the user's domain.

Since the RHC tools leverages GIT, we enable the user to create/generate ssh keys on the fly via the OpenShift Express Tool. But that newly created ssh key's public key needs to be associated to the user before it can be used. rhc-sshkey is used for that purpose on the commandline, but we don't have similar functionality in the OpenShift Express tools today. Here is what the Console should include:

Usage: rhc sshkey (<command> | --help) [<args>]
Manage multiple keys for the registered rhcloud user.

List of commands
list Display all the SSH keys for the user account
add Add SSH key to the user account
update Update SSH key for the user account
remove Remove SSH key from the user account

List of arguments
l|-rhlogin rhlogin Red Hat login (RHN or OpenShift login with OpenShift Express access) (Default: nduong+mac@redhat.com)
p|-password password RHLogin password (optional, will prompt)
i|-identifier key-name User-specified identifier for the key
k|-ssh key-filepath SSH public key filepath
d|-debug Print Debug info
h|-help Show Usage info
--config path Path of alternate config file
--timeout # Timeout, in seconds, for connection