Move braille specific classes to pef-tools

[joeha480]

Some classes are highly braille specific and might be more suitable in pef-tools (perhaps under the name braille-tools). See also brailleapps/braille-utils.pef-tools#8

[joeha480]

Currently, I think it makes more sense to deprecate pef-tools instead and allow some braille specific classes in dotify.common.