Remove Nima from DEPS, experiments, Viewer, etc.

Change-Id: Ide69d3c9f0f02e886bd0d52723d425a548edd2e0
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/214187
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
10 files changed