[FEATURE] GUI option for scaffolding apps

[swainn]

Is your feature request related to a problem? Please describe.
Don't love that quickstart creates a hello world app:

• Hard to rename apps
• Don't want quickstart to become the way of scaffolding apps

Describe the solution you'd like
There should be an option to scaffold an app from the Tethys Portal. Then the quickstart can just

Describe alternatives you've considered
N/A

Additional context
N/A

[swainn]

From our discussion in Tethys Scrum today:

• Don't like that it scaffold's Hello World (bc it is hard to rename an app)
• The quickstart should have cli options
• Add GUI option for scaffolding apps
• Overlap with idea to create dashboard apps from the app library
• Start with DEBUG = True to enable the GUI scaffolding