Adds auto variables and made rm failsafe

Variables are now used for username and email and auto populated with
values from original repos (using git config --get)
README.md removal doesn't fail anymore if the file doesn't exist.
If git doesn't return config values, previous defaults are used.

Debug messages now output deployed version (including tag).
Handles additional config file

This patch adds the ability to add an additional config file.
The intended use is to have a different variable values for deployment.

The first use case is for the 'url' config variable. Creating an
additional _config-deploy.yml file with the deployment URL, one can
transparently use development and production URLs.