khmer multiprocessing

Outstanding PR for experimenting and eventually finalizing multithreading/processing in khmer.
On Fri, Oct 24, 2014 at 07:48:30AM -0700, Camille Scott wrote:
> >          n_consumed++;
> >      }
> > -
> > +    
> > +    for (unsigned int i=0; i<s.length()-_ksize; ++i) {
> > +        
> > +    }
> > +    */
> > +    std::vector<HashIntoType> hashes;
> > +    while(!kmers.done()) { 
> > +        hashes.push_back(kmers.next());
> > +    }
> > +    #pragma omp parallel
> 
> My understanding was that the GIL doesn't come into play here because there
> aren't any python threads or references to python objects, and thus no
> python bytecode running through the interpreter; some preliminary
> performance profiling seems to indicate that's the case. I could be wrong
> though.

As you say.

Plus, it'd crash.  CPython is pretty good about crashing in this kind of
situation.