refactored TestChannel to expose fields instead of getters
added tests for Subject
moved Template class into the main project
Message uses Template to create subject and body
removed duplicated strings from tests
testing submission message subject and body
testing approval message subject and body
testing rejection message subject and body
extracted three subclasses for the three message templates
moved constants in the template subclasses
cleanup
more cleanup
even more cleanup
Uniformized constructor signature across templates (to merge them eventually)
cleanup
extracted MessageTemplate base class
moved Subject from Template to MessageTemplate
refactored Template
removed public property from Template
extracted setters in MessageTemplate