Add Graph API calls
Add Graph API calls

The graph API requires GET for some requests and POST for others. I changed
the method listing to allow specifying which API call uses GET and which uses
POST (all read only requests _should_ be using GET, so I changed those too).

In addition, some of the graph api call names are overloaded with multiple
functions (e.g. POST + id + data == edit graph, but exclude the ID and you
create a new graph), so I made separate calls for them called add_graph and
edit_graph.

omniti-labs/circus,omniti-labs/circus