Improved port inference (+ added flow sequences)

[jsoverson]

This PR improves wick's ability to infer port names so they can be omitted more frequently. Because unary components are trivial to infer, the PR also adds the ability to chain flow expressions and omit IDs more frequently, i.e. <> -> comp::op -> comp2::op2 -> <>

While adding this, I added the wick config subcommand and two sub-subcommands:
-wick config dot to generate dot syntax flow graph for a composite component.
-wick config expand to validate and output the expanded configuration that wick runs with.

This PR:

• Adds a "slow transaction" warning with active operations for transactions that last longer than 15 seconds without progressing.
• Starts operations on first packet vs starting them all at tx start. This means that downstream components no longer need to adopt the timeouts of their upstreams.
• Made wick's internal representation of configuration serializable (but not deserializable, it should always come from a v# config first).