Future of the databaseds

I started investigating the old internal databaseds package and made some fixes in !740 (merged). But there's quite a bit of work remaining before this can be used as a "drop in" replacement for the C++ Database device. I'd like to work on it!

But I also think it would be valuable to "backport" it to older PyTango versions. Not sure what the best way would be, though. The obvious alternative is to move the databaseds out of PyTango, at least in the mid term. The code is completely separated, and most PyTango users likely won't use it anyway. Eventually it might be merged back, once usage of older PyTango versions has dwindled (if that ever happens...)

(I suppose that was the plan with the Alba repo https://github.com/ALBA-Synchrotron/pytango-db but it seems it died once Tiago stopped working on PyTango. This maintenance question might be a reason to keep it inside PyTango, however that also hasn't prevented it from stagnating... maybe separating it out would make it more visible?)

Or, maybe we could build a separate package from PyTango's source code. But that might become tricky if we also want to test it against older PyTango versions (which would be the point).

What do you think?