extend doc
prepare payment method API docs
For #143: add principal status schema
add principal status field
fixes #145
implement insert principal status, remove unused insert principal db
Principal.Active() method
add failing test, principals without status cannot be selected
select principal requires status
deleted principals not in selected sets
principal API test: add failing test, status must be set on
create principal.
support for verifying invalid statuses
support principal status on create principal API request
Merge pull request #146 from wongak/extend_doc

Extend doc
Merge pull request #147 from chruffer/refactor_project_method

fixes #145
Merge pull request #149 from wongak/143-principal_status

Add principal status functionality