Ruby

[ruby/irb] Powerup show_source by enabling RubyVM.keep_script_lines
(https://github.com/ruby/irb/pull/862)

• Powerup show_source by enabling RubyVM.keep_script_lines

• Add file_content field to avoid reading file twice while show_source

• Change path passed to eval, don't change irb_path.

• Encapsulate source coloring logic and binary file check insode class Source

• Add edit command testcase when irb_path does not exist

• Memoize irb_path existence to reduce file existence check calculating eval_path

https://github.com/ruby/irb/commit/239683a937