Fix graph routes

[deepakunni3]

Fix implementation of graph/node/<id> and graph/edges/from/<id> routes.

This PR will change the behavior of graph/edges/from/<id>.

Previously this route would,

• fetch edges with relation subClassOf, direction OUTGOING, and depth of 20
• fetch edges with relation subClassOf, direction INCOMING, and depth of 1
• fetch edges with relation equivalentClass, and depth of 1

This PR simplifies the behavior of graph/edges/from/<id> where it now acts as a simple pass through to SciGraph graph/neighbors endpoint and makes no assumption about relation, direction or depth.

[kshefchek]

couple of linting considerations but otherwise looks good, +1

[deepakunni3]

Thanks @kshefchek

I'll incorporate the suggested changes.