Add graph_by_name? helper method to determine if there is a graph with specified name
Remove protected so that the pre_verify following actually runs
Add helper method filter_for_graph that simplifies defining a filter from a struct
Add equiv? on FilterParameter so we can compare two parameters to see if they are equivalent
Improve the error message in verify
Cleanup whitespace
Name parameter appropriately
Rework graph links so that they are modelled using a class rather than a hash. Add significantly more validation to graph links
Improve the documentation generated for graphs so both inward and outward graph links are documented