appended target for lint and fix
appended gemnasium badge
fixed description for README.md
rewrote unit test of mkrand
rewrote unit test of mktemp
appended test for private methods
added benchmark
appended npm-script for benchmark
changed to fast code
some changed

- changed from comment to doc comment
- changed function and exports
appended doc comments
some changed

- added lib/index.js
- appended export interface test
changed benchmark

- appended
- refactored