created the priority queue heap thing with tests
fixed extra line issue
restructured tests
refactored code
added peek method and corresponding test
actually added peak method, small formatting changes
Add .travis.yml and requirements.txt for Travis testing.
Merge branch 'priority-queue'
Merge branch 'simple_graph'
Create TraversableGraph() in traversable_graph.py and import required modules to the local dir.
Add TraversableGraph.depth_first_traversal() to progress through connected nodes in a depth first manner
Add TraversableGraph.breadth_first_traversal() to progress through connected nodes in a breadth first manner.
Add name==main block demonstrating traversals of some graphs
moved this copy of simple_graph to make import easier
added line spacing
Wrote the tests!
Update README.md to include TraversableGraph()
Merge branch 'traversable_graph' of https://github.com/jefrailey/data-structures into traversable_graph
added a simple dictionary of edge weights that allows for bidirectional weights
added simple tests for edge weights