Update the module documentation
Relates: #424
There are two (duplicate) sections about local DDEV development in the documentation. I'm not sure if the first one has been added recently, or has been there a long time. If there is helpful information in it, perhaps it can be merged with the more detailed section, at the bottom of the documentation.
For details about the changes these additions describe please ask @dreizwo.
Edited by John Durance