- add a reference Dockerfile to tools
- update kata-monitor build to:
1) utilize the kata buildflags, which were dropped before
2) disable CGO, so we have option for building in alpine
From root of the repository, example build:
$ docker build -f tools/packaging/kata-monitor/Dockerfile -t kata-monitor .
Fixes: #1135
Signed-off-by: Eric Ernst <eric.g.ernst@gmail.com>
