Changed Task.add! to use smart add option by default.

Modified the RTM API call to include a parse=1 option by default.  Task.add!
now takes an options hash including :list_id and :parse.  Call Task.add! with a
:parse => false option to disable smart add.
Merge pull request #3 from jleverenz/default-smart-add

change Task.add! to use smart add option by default.