Add treble_build command with report and outputs sub-commands

report:
Report the projects and source files used to build the given targets.

outputs:
For a given set of commits (project:sha), get the corresponding source
files.  Translate the source files into a set of outputs and optionally
build outputs.

Test: m treble_build
Test: treble_build report droid
Test: treble_build report -v -o out/droid_report.txt droid
Test: treble_build report -json -o out/droid_report.json droid

Test: treble_build outputs -repo platform/frameworks/av:HEAD^2
Test: treble_build outputs -repo platform/frameworks/av:HEAD^2 -build

Bug: 213174560
Bug: 230097250
Change-Id: I8b6c5ad2356d9ba8327d0baffc191732a601cafe
24 files changed