Merge pull request #2 from mcruthven/master

dijkstra algorithm
Merge pull request #3 from mcruthven/master

use the vertex weight attribute in dijkstra algorithm
ADD: Preliminary vertex weight calculation
Merge branch 'master' of https://github.com/alexadkins/Catan-Pathfinder
Merge pull request #4 from mcruthven/master

fix tests and tabs
ADD: Vertex weight refactor
ADD: GUI selecting start and end points
ADD: Controller and dijkstra's algo
FIX: Moved tests in main to tests.py
Merge pull request #5 from mcruthven/master

Handle None vertices
style