use commonJS modules for preprocessors
catch uncaught exceptions (oh no no no)
update preprocessor by clearing require cache
workerFarm implementation
update workerFarm
use SparkartGroupInc branch of node-worker-farm
update to use latest node-worker-farm

update tests
add link to preprocessor docs
update preprocessor documentation
default to log level 2 when run from terminal command
use a more unique underscore method in example
properly log preprocessor errors