Move image upload part from api recipe to new recipe of image_upload.

Since for bug 1257169 openstack-image api recipe should be executed before
openstack-image registry recipe, the image upload part in the api recipe need
to be moved to a new recipe of image_upload.

Change-Id: I1f557d2e817643a9e3e06788dc446c970ef2df89
Closes-Bug: #1257169