Color details view links differently based on contract type

[crpc]

Scope

Right now links are colored the same way no matter what the contract type between two nodes is. Information about different contract types should be visually presented (different colors seem to work best in this case).

Details

Since there could potentially be infinite types of contracts and information about them should be consistent (should not change between sessions - this is why colors can't be generated on the fly), there should be a general classifier function which would return prepared colors for known types of contracts (like rest or jms) and return one color for all unspecified types of contracts.