Improve docs for item_types
Improve docs for item_types

tribut/vdirsyncer,credativUK/vdirsyncer,untitaker/vdirsyncer,mathstuf/vdirsyncer,credativUK/vdirsyncer,hobarrera/vdirsyncer,mathstuf/vdirsyncer,hobarrera/vdirsyncer,untitaker/vdirsyncer,tribut/vdirsyncer,untitaker/vdirsyncer