Exploration.alg: Add Channels Export for Partitions.

* Adds a sub-method to the Partition Transformation Strategy that adds Ports and Channels to a PartitionAchitecture.
* The required Ports and Channels are derived from the Signals exchanged between Tasks.
* Ports and Channels are only added for InterPartitionCommunication (logically).
* The Sampling and Queuing characteristics of PartitionPorts is derived from their corresponding TaskPorts.
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