The same-state redirect (when there is a request for the current executing
state that causes it to redirect back to the top of the state and reexecute
the main method) is somewhat unintuitive and has caused problems:

#18

This change requires that an edge exist from a state to itself in order
for a same-state redirect to take place place, e.g.:

edge = [('STATE', 'STATE')]

A new test was added for this change.