Add custom quasar that imports from a source

[KenEucker]

It would be nice to have a 'custom' quasar option that imports a new quasar from a zip file. The contents should be the assets folder with template files and a configuration file that defines the actions to run, the required parameters to prompt for, and the default arguments for the quasar. The quasar will be built as a copy of the 'page' quasar following the same format.