Adds support for TableDAP and DAP Sequences OOIION-1405

Part of [OOIION-1405](https://jira.oceanobservatories.org/tasks/browse/OOIION-1405)
The other parts are:
 - Coverage deepcopy optimization, will be released after this is integrated with ion_alpha
 - Improving the performance in PyDAP's serialization mechanics for dods requests for sequences, it's too slow for semi-large datasets. Up to 60s for a 22000 timestep dataset. Numpy can do the heavy lifting.