back2source: Extend ScanCode.io pipeline for Ruby source and gem packages

[pombredanne]

Create a new set of pipelines steps for the binary to source analysis for Ruby source and gem packages using strings and symbols

[pombredanne]

There a few rarer oddities that may need separate tracking in a future issues:

• gem with "native" code delivered as C/C++ ... here the compilation may happen at install time? we may need to do some ELF or related analysis. See https://rubygems.org/gems/sha3 or https://rubygems.org/gems/java_bin
• gem with platform=java that are designed to work on JRuby only with a <name>-<version>-java.gem name as in https://rubygems.org/gems/java_override or a jubdy suffix as in https://rubygems.org/gems/java_gem at https://rubygems.org/downloads/java_gem-0.1.0-jruby.gem
• gen with bundled JARs https://rubygems.org/gems/bouncy-castle-java

[AyanSinhaMahapatra]

This was completed with:

• Add ecosystem specific inclusions or exclusions #1550

See the related pipe in SCIO documentation: https://scancodeio.readthedocs.io/en/latest/built-in-pipelines.html#scanpipe.pipelines.deploy_to_develop.DeployToDevelop.map_ruby

This is available as a new optional step in the deploy_to_develop pipeline: Ruby (you can select this through the UI or pass this as an option when using the API/CLI: deploy_to_develop:Ruby )

Select the option Ruby in the new project form like this: