Rename a directory from 'js' to 'lib'.
Move the 'css' directory to the 'lib' directory.
Move the 'image' directory to the 'lib/css' directory.
Remove unused images.
Unify name of images for button icons.
Merge pull request #47 from pubannotation/lib_directory

Create a directory 'lib' to contains textae files of JavaScript, css and images.