Monologger for lock-less logging
extract configurator to a new file, provide validation of params, set default logger, allow custom logger
move monologge require to the correct location
extract engine name finder a bit
try to keep logging out of spec output
move some stuff to private from top-level, abstract getting the engine config
warn on engine selection
log poller pretty heavily
only delete message on pop if mesage block returns true
log engine
default to error log level
update readme
also require that logger respond_to :level - that should be the only other method we care about
move default log test to use ERROR
allow validation messages to be customized
switch default to :debug on Poller and make customizable
still use warn on poll-kill
Merge remote-tracking branch 'origin/master' into loggify

Conflicts:
	lib/queuel/base/poller.rb
woops, wrong method?
fix message spec