:construction:  Ruby bindings!

:construction: :construction: 
This is the start of the ruby bindings. 

So far we support the following libcsg functions 

* stl_read_file
* stl_write_file
* stl_to_bsp
* bsp_to_stl
* bsp_intersect
* bsp_union 
* bsp_substract 

:tada: