Add jit code cache directory to classpath.
See Issue https://github.com/jruby/jruby/issues/1585
-------
I'm using jruby 1.7.11 (1.9.3p392) 2014-02-24 86339bb on Java HotSpot(TM) Client VM 1.7.0_10-b18 [Windows XP-x86]

I run
jruby -Xcompile.mode=FORCE -Xjit.debug=true -Xjit.codeCache=c:\tmp test.rb
and many

... Ruby: no jitted code in classloader for ...
... JITCompiler: writing jitted code to to ...
will be printed. And in the rerun the same, but the cached files exists in the directory.
I looked into the source and I found that the JRubyClassLoader is used to load the cached classes. But I can't find the location in the code where the codeCache directory is added to the JRubyClassLoader.
After I patched the getJRubyClassLoader method in the Ruby class, and add the code cache directory to the Classloader, everything works fine for me.