Add Ruby file extension to Ruby from Other Languages

[Oisins]

As a ruby beginner reading the help pages I would recommend adding something like: "In comparison to Python, Ruby files have the extension .rb" to the Ruby from Other Languages page.

[DanRathbun]

To which, I scratch my head in bemusement wondering, .. "What possible file extension could Python be using for Ruby files ?"

;) J/K

Perhaps "In Ruby, script files use the .rb extension." is better ?

We cannot use the words "source files" because ruby libraries can be written in C / C++ (as well as other langauges,) and compiled to .so,.dll,.dylib, etc.

[Oisins]

Sounds good.