Update linker to support link dependencies

[njgheorghita]

What was wrong?

linker was not adding link_dependencies to manifests of newly created deployments that contained link references.

How was it fixed?

• Requires runtime_bytecode to be present in contract type in manifest
• Yanks link_references from runtime_bytecode and uses those to populate link_dependencies data
• Started to update docs to reflect changes in library

Cute Animal Picture

[njgheorghita]

@pipermerriam ping in case this got lost in the noise