Use same version for all versions of ruby 1.9.x

Author: francoisjacques

ext/mkrf_conf.rb

@@ -19,10 +19,8 @@ def already_installed(dep)
 
   if RUBY_VERSION < "1.9"
     dep = Gem::Dependency.new("ruby-debug-base", '>=0.10.4')
-  elsif RUBY_VERSION >= '1.9.3'
-    dep = Gem::Dependency.new("ruby-debug-base19x", '>=0.11.30.pre15')
   elsif RUBY_VERSION < '2.0'
-    dep = Gem::Dependency.new("ruby-debug-base19x", '>=0.11.24')
+    dep = Gem::Dependency.new("ruby-debug-base19x", '>=0.11.30.pre15')
   else    
     dep = Gem::Dependency.new("debase", '> 0')
   end