Scope

Implement all the code changes to pass image size to glance API and make it ready for review in upstream.

Acceptance criteria

1. Patch code should for review in upstream
2. It should have all unit and/or tempest tests if required

Enable the use of the --size option for the image-upload and image-stage commands, as well as to add this option to the image-create command. The image size will be calculated automatically if a file-like object is detected during the upload or staging operations. Otherwise, users can specify the image size via the --size command-line option. If the --size option is provided, we will not calculate the image size internally, and the user-specified size will be sent directly to the Glance API. We will introduce a new request header `x-image-meta-size` which will be passed to API.