fix V1 register

BACKGROUND:

$ vmc -v
vmc 0.5.0.rc1
$ vmc target api.cf100.dev.las01.vcsops.com
Setting target to https://api.cf100.dev.las01.vcsops.com... OK
$ vmc register admin@vmware.com --password password
Confirm Password> ********
NoMethodError: undefined method `password_score' for #<CFoundry::V1::Client:0x00000002a2b258>
For more information, see ~/.vmc/crash

TEST PLAN: verified against old-CC
$ vmc target
target: https://api.cf100.dev.las01.vcsops.com
$ vmc register admin@vmware.com --password password
Confirm Password> ********
Your password strength is: good
Creating user... OK
target: https://api.cf100.dev.las01.vcsops.com
Authenticating... OK