Enable better code parallelization

 - Sets the swig binding cxx files as dependencies on the parent swig
   target
 - This allows the cmake generator to parallelize the generation of swig
   bindings

Uses more ram and is potentially annoying to the developer since the cxx
files generate before any code starts compiling. Could make regeneration
and rebuilds annoying / painful

enable MAXIMIZE_CPU_USAGE (advanced setting) to test