1. Collapses the "including .../Android.mk ..." lines like ninja does,
so that we overwrite the last line if there wasn't anything else to
print.
2. Strips ansi control codes so that log files don't include unreadable
characters.
Test: m -j
Test: m -j | tee output.log (with colored output)
Change-Id: Ib18437f6f9d37084360097a9d586800c833072c5
