Guides and Undirected Update

Two new features:

• Guides: the tool now includes a Guide button, which will provide a manual on how to use it. The first page is a general guide, while the second page is a guide on the specific tool selected (e.g. Graphs, Disjoint Sets, etc...)
• Undirected graphs: convert graphs to undirected by unchecking the "Directed" option (note: switching from Directed to Undirected or vice-versa will delete all edges); can run Minimum Spanning Tree algorithms on the undirected graphs