Atest: move src tree to tools/asuite

This is just a copy of tools/tradefederation/core/atest. Note that
tools/tradefederation/core/atest/Android.bp is not copied; also, the
asuite_lib_test/ is not copied to avoid duplicate target names.
we'll deal with modules at the last phase of migration.

Bug: b/144140286

Test: None
Change-Id: If8cdec8b7c35dd735195def470156687693a445b
126 files changed