The v3 credentials passes data associated with the credential in
a "data" key, but the underlying API expects "blob", which is also
what is documented in the API spec.
Currently any attempt to create a credential with a type of 'ec2'
will fail with 'Invalid blob in credential' So s/data/blob to fix.
Change-Id: I0858e8c39653477eb554ee9d15fb4f2dde2b195c
Closes-Bug: #1259461