Don't write .ep_initialized in source directories

In my installation I install Etherpad without giving write permissions to the node processor over the source directory. It seems this is a problem because Etherpad tries to write to four places:

• APIKEY.txt (OK, I can generate this in advance)
• SESSIONKEY.txt (I can generate this as well)
• var/ (this is easy to make writable by node process)
• .ep_initialized in each plugin directory – this is hard to do without giving write access to all plugin code

So why is .ep_initialized needed? It seems it is only created once, but never really cleaned up?

[mitar]

No time at the moment, but eventually yes, if somebody else does not do it earlier.

[mitar]

I realized that this is even more problematic with Docker containers then it appears. Namely every time you create a Docker container (based of some Docker image) its files are recreated. So even if you make it so that .ep_initialized can be written into the container, the next you create the container (e.g., upgrade Docker image) files are gone. It is hard to make whole source directory into a persisted volume because then code will also not upgrade. Moving these files to var directory might be reasonable, because then I can at least make var directory a persisted volume.

But primarily I do not buy that it would not be better to write this into a database. If database is not available on startup, Etherpad should not start (and then a supervisor can retry it). Everything else is in the database and is required to be there for Etherpad to work, why not also these flags?