Delete all of the tools/ directory, but save the adk files by moving them up.

Redirects for all the tools/ files are already in Piper's site-android/en/_redirects.yaml file.
The new adk redirects are in this cl: https://critique.corp.google.com/#review/121302608

Change-Id: Iaec963429274d617572d4a23549de1b561932c44