Zoo Workflow: Combine the extract shorelines step with model step

[2320sharon]

It's very easy for users to get confused or mislabel sessions when extracting shorelines. After our meeting today we think it would be better to combine the step where the model is applied with the step where the shorelines are extracted. This is how it's done in the coastsat workflow and this helps mitigate the odds a user will make a mistake or forget which session to use.