Makes the image registration/upload an LWRP

Adds a slightly modified version of the RCBOPS glance_image
LWRP. This cleans up a bunch of stuff in the glance::api
recipe and makes it much easier to read and diagnose.
Reversed resource and provider :(
Chef+Ruby local variable scope is retarded.
Merge pull request #62 from jaypipes/image-lwrp

Makes the image registration/upload an LWRP