Remove spec task from Rakefile
Remove spec task from Rakefile

This should avoid rake to run all test suite twice.

igrigorik/vimgolf,urticadioica/vimgolf,igrigorik/vimgolf,igrigorik/vimgolf,igrigorik/vimgolf,urticadioica/vimgolf,urticadioica/vimgolf