version.rb in lbfgsb-0.5.0

- old
+ new

@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
 # Lbfgsb.rb is a Ruby binding for L-BFGS-B with Numo::NArray.
 module Lbfgsb
   # The version of Lbfgsb.rb you are using.
-  VERSION = '0.4.1'
+  VERSION = '0.5.0'
 end