Add custom template support

[erlendwtf]

It would be a killer feature if we could add our own custom templates (and even disable the public templates) to run DCM as an "À la carte" menu for in-house Docker images.

Scenario:
A user needs to configure a server consisting of our in-house software, App A, B, D and H.
Instead of us needing to maintain N number of permutations of pre-made compose files, for every single scenario of app variations, the user simply selects the software from DCM, enters the required information for the services (if required by a given service), and downloads the generated compose.yml.

[ajnart]

Interesting discussion @erlendwtf , you are self-hosting DCM?

I didn't think someone would self-host.

I guess we could have some dynamic feature to add containers by yourself on self hosted, but on the web version it might be a little bit harder since there is no database. I think we can encode the whole data within the URL but I'm not 100% sure about it

[erlendwtf]

Correct, I would only expect such a feature for self-hosted DCM to begin with - we will only be self-hosting anyway. :)