Modifiying default to accept a function or value
Matching coding style
Removing un-used method and variable
Defaults should not override non object, array or string values.

The method _.isEmpty() will return true for numeric values as well as for dates and booleans.

The following patch (test case included) fixes that by using some extra logic for determining wether a value is empty or not.
Merge pull request #6 from plus3network/master

Modify default to accept a function or value
Merge pull request #7 from bermi/master

Removing un-used method and variable
Merge pull request #11 from ekeitho/master

Fixed README DOC
merged isEmpty change to isEmptyValue
Merge branch 'bermi-default-stepping-on-numbers'
fixed merge conflicts