promisified load/store
promisified .open & .create
finished promisification methinks
added err() and repeatStr()
fixed failure to pass props to new Segment call
* fixed failure to pass props object into new Segment calls.
* made store() take optional hdl location parameter.
* increased RunningAverage stats nelts to 1000 from default 10.
tweaked lengths of data files
added 1k file for tests to use
tweaks
added test for non-default metaProps values; it flushed out some errors