Initial attempt to reduce memory

Lots of reporting is broken. See the TODO's
Change constructor to use simple subset list
Cleanup unused functions and whitespace
Greedy Algorithm working with new low memory
Simplify what we compare in results.py
All Schemes now works with low memory
Progress now handles more output
User schemes fixed.
Cleanup
fixed greediest analysis

and took out all the bugs that Brett Calcott put in.
better reporting for users
fixed scheme writing in greediest algorithm
changed subset counter for now
report progress again

seems to reveal a bug elsewhere. Are we adding identical subsets?
nothing
clunky fix for progress reporting

the real problem seems to be that subsets don't remember that they're
DONE. So, if I recreate an existing subset, the factory appears to load
it up, but that subset doesn't know that it was already done.

This workaround is bad, because it keeps a set of subsets, which takes
too much memory.

We need a better fix. Not sure what.
reinstated subset counter in greediest algorithm
just keep subset names for progress

now we are back to being very memory efficient
counting schemes and subsets in greediest

is now done. It's interesting. The functions have 'output' flags in
case I ever want to draw the graphs.
removed scheme progress