Log Message:
devel/ruby2ruby: update to 2.4.2

=== 2.4.0 / 2019-03-12

* 3 bug fixes:

  * Fixed sexp_body to return empty sexp instead of nil when using STRICT_SEXP.
  * STRICT_SEXP=4+ fails w/ current use of concat. Removed concat from \ 
strictness for now.
  * Use concat internally instead of splat. Some people have 20000 node sexps! \ 
(presidentbeef)