Configuration File as Option

[Andrea Lamparelli]

Since the number of CLI options is increasing more and more, give users the possibility to provide a json configuration file containing all those required options.

Option: ".option(--config <path-to-config>", "path to a configuration file containing all required options", undefined)

Config file example:

{
  "target-branch": "<branch>",
  "pull-request": "<pr-url>",
  "auth": "<token>",
  ...
}