Spelling
Added 'not:' data source filtering support

This make it possible to exclude entries based on the field's value.
It does works both with and operation (not x and not y) and or operation (not: x, y).
version bump to 1.2.1
Merge pull request #20 from DeuxHuitHuit/not-filter

'not:' filter
Credit
Version bump
Fixed version
Merge pull request #23 from nathanhornby/integration

Integration