Move JRuby's ext and loader script

* ext/java => ext/jruby
* lib/jruby/strscan.rb => ext/jruby/lib/strscan.rb
* Changes to Rakefile and gemspec for new locations

Fixes #38

Author: headius

Rakefile

@@ -21,7 +21,7 @@ if RUBY_ENGINE == "jruby"
     require 'maven/ruby/maven'
     ext.source_version = '1.8'
     ext.target_version = '1.8'
-    ext.ext_dir = 'ext/java'
+    ext.ext_dir = 'ext/jruby'
   end
 elsif RUBY_ENGINE == "ruby"
   require 'rake/extensiontask'

lib/jruby/strscan.rb ext/jruby/lib/strscan.rblib/jruby/strscan.rb renamed to ext/jruby/lib/strscan.rb

@@ -17,7 +17,7 @@ Gem::Specification.new do |s|
   s.description = "Provides lexical scanning operations on a String."
 
   if RUBY_ENGINE == 'jruby'
-    s.require_paths = %w{lib/jruby lib}
+    s.require_paths = %w{ext/jruby/lib lib}
     s.files = %w{lib/strscan.jar lib/jruby/strscan.rb}
     s.platform = "java"
   else