The --source-roots Parameter Should Optionally Be File-Based

[jisedlac]

Listing all source roots using the --source-roots parameter may easily hit the limit of command line length.
Should allow defining the source roots in an external file and just point to that file.

[jisedlac]

Implemented: --source-config="path_to_config_file" where the config file is a file created using java.util.Properties.store() with the UTF-8 format, containing two properties source-roots and source-viewer with the same values as for the regular arguments.