Let us start registering the existing option. I'm starting with the 'devel'
section because it is full of useful things that are poorly documented. So
registering these will more than other section.
Yuya pointed out that using mutable value as the default could be problematic.
To work around this we now support callable object as default value. This
allows for creating new mutable objects on demand when needed.
Extensions can have a 'configtable' mapping and use
'registrar.configitem(table)' to retrieve the registration function.
This behave in the same way as the other way for extensions to register new
items (commands, colors, etc).
The goal of this class is allow explicit declaration for the available config
option. This class will hold the data for one specific config item.
To keep it simple we start centralizing the handling of the default config value.
In the future we can expect more data to be carried on this class. For example:
- documentation,
- status (experimental, advanced, normal, deprecated),
- aliases,
- expected type,
- etc...
