Switch to following spec for to/from rules.

Used to use:
<apps:property name='hasTheWord' value='to:postman@usps.gov'></apps:property>

Now uses:
<apps:property name='to' value='postman@usps.gov'></apps:property>
Interact properly with otherwise directive

Also works for blank directives.
Add tests for to/from handling
add gmail smart label support
update examples/asf.rb to show some smart_label usage
added subject support from commit d367df25aa77eab5288c479dd2557aa9919a60a7 in https://github.com/jabley/gmail-britta