prep for v0.4 alpha --KW
more v0.4-alpha prep, removed methods that are not ready for primetime (mode, _distinct); code tested for compilation but not tested on live Arduino yet --KW
checkin before new internal data structure implementation --KW
put(), describe(), and mean() work and are tested on Uno --KW
minimum() and maximum work and are tested on Uno --KW
stdev() works and is tested on Uno --KW
v0.4 release --KW