fixes tuple pretty-printer
fixes memo printing
switch test_base to nose.tool assertions
tests string output for `memo`
tests tuple pretty printer
tests memoizer
tests memo_sqrt
tests maxwalksat
removes symbollog

it was holding me back anyway
adds html for homework specs
cleans up symbollog tests
flake8 fixes for tests
fixes random_index err message
removes unused import
fixes whitespace in base
moves io calculation to model where it belongs
deals with fallout from moving IO object
reimplements _sample_frontier_exclude, adds docstring
consolidates logging config vars
adds error-throwing on NumberLog.better