cvetriager: added logging statements

Modified print statements and added logging statements for debugging
purposes. Also made small fix to contextgenerator_test.py because test
started failing after refreshing kernel repos.

BUG=chromium:1093363
TEST=python setup.py test

Change-Id: I8da80571b65ba9a108b8f498e6685af21574b3c5
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/2292934
Commit-Queue: Wanda Mora <morawand@chromium.org>
Tested-by: Wanda Mora <morawand@chromium.org>
Reviewed-by: Zubin Mithra <zsm@chromium.org>
7 files changed