Update bison to 3.0.4

This is a general bugfix/maintenance release.

Tested as working on Samsung XE50013-K01US.

All tests are passing.
https://gist.github.com/cstrouse/119ccdd427696b4662486c3b6cf12606

packages/bison.rb

 require 'package'
 
 class Bison < Package
-  version '3.0.2'
-  source_url 'http://mirror.keystealth.org/gnu/bison/bison-3.0.2.tar.gz'
-  source_sha1 '4bbb9a1bdc7e4328eb4e6ef2479b3fe15cc49e54'
+  version '3.0.4'
+  source_url 'http://mirror.keystealth.org/gnu/bison/bison-3.0.4.tar.gz'
+  source_sha1 'ec1f2706a7cfedda06d29dc394b03e092a1e1b74'
 
   depends_on 'diffutils'
   depends_on 'm4'