be almost just like etsy statsd

* submit rates, not counts
* more stats for timers
* use config file
* configurable prefixes, default to legacy
* don't do that weird counters hack that is unclear what
  it's for and shouldn't be needed anyway.
support floats as input

for now, just convert them to ints, which is not the best..
also, debug messages for invalid lines
ignore tests
actually, just make all inputs (and hence most outputs) floats

this is how statsd does it, and people come to expect it.
for example swift submits rational numbers for timings,
and there's technically no reason to only use ints for any
of the metric types
accuracy fix
support cpu profiling
instrument (# metrics and ms) individual processor functions
more performant line parsing

using []byte and string operations instead of regex
cuts off about 25% of cpu time.
support all signals, in particular SIGINT ! (ctrl-C)
bugfix: count/count_ps must be adjusted for sample rate
support memory profiling
api interface to get ideal sample rate

using an admin interface like etsy statsd has
bugfix: calculation time was 1000x too high

instead of being suprisingly slow it's now suprisingly fast :]
clearer error
provide `metric_stats` admin command to get details about metric

rename some channels and types for their new meaning / more clarity
update README