Log Message:
misc/ruby-slop: update to 4.7.0

Update ruby-slop to 4.7.0.

pkgsr change: Add "USE_LANGUAGES=	# none".

v4.7.0 (2019-06-29)
-------------------

Features:
  * Add `Slop::Result#fetch`. It returns the value of given option, or raises an \ 
error if given option is not present. \ 
[#232](https://github.com/leejarvis/slop/pull/232) ([Giovanni \ 
Benussi](https://github.com/giovannibenussi))
  * Adding a separator without passing any arguments now creates a separator \ 
with the empty string. [#238](https://github.com/leejarvis/slop/pull/238) \ 
([Teemu Matilainen](https://github.com/tmatilai))
Bug fixes
  * Ensure non-string option types have their flags consumed properly [#241] \ 
(Sutou Kouhei)