Define new Phase Descriptions

As part of https://github.com/open-rmf/rmf_ros2/issues/107 we should start defining the Descriptions of the new Phase types.

We could start immediately on these task types:

• PerformAction (we will need the Description to have a parameter for an estimated duration for the action)
• ParkUntil (we will need the Description to have a parameter for an estimated duration of the parking)
• Call
• SMS
• RepeatN
• While (we will need the Description to have a parameter for an estimated number of repetitions so the planner can deal with this phase)
• ParallelGroup

This phase will require https://github.com/open-rmf/rmf_task/issues/42 before we can support it:

• RepeatIndefinitely

The APIs for these different phase Descriptions should be put into the rmf_task_sequence/phases include directory.