Static linking all dependent libraries into each ruby version (from
1.8 to 2.2) would blow up the gem to >20MB.

Before commit af543822 loading order of fox16.so and fox16.rb was irrelevant.
But now fox16.rb must be called, in order to load ruby files to the C++
extension. Renaming the C++ extension ensures, that fox16.rb is called first.

C++ source and header files.