Ruby

[ruby/irb] Decouple edit and show_source commands
(https://github.com/ruby/irb/pull/658)

• Decouple edit command from show_source

2 commands should not depend on each other. If edit command also needs
to find a source, the source finding logic should be extracted into a
separate class.

• Return nil if is not an actual file path

• Refactor SourceFinder

https://github.com/ruby/irb/commit/9790517a0c