Change in structure for Filter and the way the Header is returned.
Added new setter methods. Replaced implementation of some Setter methods to more strict ones
Added new test for AddTO
New Test for creating header object
Test AddTos and incorrect test name fix
Added TestSetTos
Added TestAddSubstitution
Added TestAddSubstitutions
Added TestSetSubstitutions
Added Test methods for Section
Added Tests for Categories
Added Tests for UniqueArgs
Go convention discards _ in variable names (Unique_args) and lowercase json (JsonString Method)
Added Tests for Filters
Stable release