Merge pull request #1 from matthewbdaly/master

Extended unit tests
Merge pull request #2 from matthewbdaly/master

Further unit tests
Merge pull request #3 from matthewbdaly/master

Added unit tests to example
Merge pull request #5 from matthewbdaly/master

Test title
Update jquery.listfilter.js

Callback function added , it can be used by 'callback' option
Update jquery.listfilter.min.js

minified version with callback
Update README.md
Merge pull request #7 from ex7r3me/master

Adding Callback funtion
Amended tests to work with Testem
Amended README
Added unit test for the callbacks