tblobaum/stats-array — pull request #1 by pedrombafonso (2014-01-21 15:08:30+00:00)
Title: new method: marginOfError

Hi @tblobaum

Thanks for this module!

### New method:
```
maginOfError(confidence)
```
- developed it according to this formula: http://www.wikihow.com/Calculate-Confidence-Interval
- used this library for calculating Z value distribution: https://gist.github.com/benrasmusen/1261977 (node.js: https://gist.github.com/pedrombafonso/8541077)
- [x] Added tests
- [x] Updated the documentation