Proposal: implement a minimal build script to add VERSION and GITCOMMIT

This PR implements a minimal build script to include VERSION and GITCOMMIT into the executable. Similarly to `Docker`, the build script is placed under `project/make.sh`, the VERSION file must be existed in the code directory. GITCOMMIT is detected using codes from `Docker`.

The API `/version` is also tweaked to return proper VERSION and GITCOMMIT values.

In the client app, the version is composed from VERSION + ", gitcommit: " + GITCOMMIT.

Signed-off-by: Chanwit Kaewkasi <chanwit@gmail.com>