Missing documentation on build, deploy commands

[basilv]

Top level documentation (e.g. https://github.com/bcdevops/nrdk or https://www.npmjs.com/package/@bcgov/nrdk) doesn't discuss the nrdk build or deploy commands. (Running nrdk help build or nrdk help deploy does provide information on the arguments to these commands.)

On a related note, would also be beneficial to have higher level documentation on the purpose of nrdk and typical usage in defining a pipeline in Jenkins, with associated branches in git and associated issues in JIRA.

[basilv]

Would also be nice to have better logging/error messages. E.g. if nrdk build fails for a build with multiple build templates, it isn't obvious in the log which specific build template had the failure.