Fixed readline issue of irb in maemo ruby for n810

It's very annoying that the irb in maemo does not support the readline feature.

Finally, I resolved this!

Steps:

1. Install libreadline5 and libreadline5-dev, depends on libncurses5
   


2. download ruby source code: ruby_1_8
   


3. cd (ruby_src_dir)/ext/readline
   


4. ruby extconf.rb
   


5. make
   


6. sudo make install
   

Done! Enjoy ruby!