Fix clojure.org recipe (Issue #14) and Rakefile added

I tried to figure out what was the problem of the clojure.org recipe and I come out with this super simple commit.

I think that each recipe should contain an full description of what they are supposed to do. In this case I do not know if the result that I get with this scarper is the equivalent of the old one.

Hope you enjoy the shortest commit ever :)

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The second commit adds a Rakefile.
The Rakefile now has two tasks:

1) rake / rake list
It shows all recipes available in the repository.

2) rake compile[recipe_name.rb]
It compile the recipe given as argument to the rake task.
Note that with some shell (for example zsh) you have to type:

rake 'compile[recipe_name.rb]'

to execute the task correctly.