bug#30075: etags misdetects ruby sharp-bang sequence

[Eli Zaretskii]

> From: Dmitry Gutov <dgutov@yandex.ru>
> Date: Thu, 11 Jan 2018 02:36:55 +0300
> 
> Here's a file that is parsed wrongly when it has no .rb extension. The 
> sharp-bang sequence at the top looks correct to me.

No one taught etags the name(s) of the Ruby interpreter(s), and nobody
told it about the "#!/usr/bin/env FOO" way of specifying an interpreter.

Should be fixed now on the emacs-26 branch.

Thanks.