Merge branch 'release/0.3.1' into develop
Adding ability to generate from normal distribution
Need to make sure that options exists
Fixed .integer() to calculate correct range.

(was using options.min in both places).
Add a test for the case @path411 found of the min being used twice to calculate the range of int values
Update to integrate travis-ci
Add Travis build status badge to README
Add first, last, fix prefix bug for name
Fix issue #5 found by @nicolashery where a natural with both bounds 0 returned unexpected results
Bump version number
Merge branch 'release/0.3.2' into develop
Add feature to get area code without parens
Added main property in package.json

Since the main chancejs library file is not named index.js or index.node (see http://nodejs.org/api/modules.html#modules_folders_as_modules ), this is needed so that the library can be found via require().
Add Luhn algorithm
Add basic credit card number generator
Add basic credit card types
Get cc type with associated data
Use cc_type() to generate cc_number()
Fix credit-card test
Rename `type` as `name` in  cc_types()