SkQP: consolidate cut_release scripts

replace the following scripts: cut_release, get_gold_results.py,
goldgetter.py, make_rendertests_list.py, and upload_model with a single
program: cut_release.  Still depends on three C++ programs: jitter_gms,
list_gpu_unit_tests, and make_skqp_model.

Change-Id: I28f59bc1f0caedc05d6ce2c4cc11bbd66cfb9784
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/209171
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>
7 files changed