Cannot create 'default' section about crudini

[pixelb]

Indeed :(

This looks to be an issue in iniparse.
It doesn't treat "default" specially when reading, so I don't know why it's restricting creation of such a section.
I guess it's for compat with other parsers.
I see ConfigParser has similar restrictions, so I guess it's trying to avoid compat issues with it:
https://stackoverflow.com/questions/25628651/write-to-lowercase-default-section-configparser/52217359
I also see iniparse hardcodes "default" rather than using its DEFAULTSECT definition.

As a workaround we could check case variations of "default" and change to "default_crudini_remove_when_writing".
We already do similar string replacements on write.

I'll need to look into compat issues though a bit, before doing this