Allows preset "All" to be written in kritarc
This is a hack as resource manager is been rewritten. The tag only needs to be written to kritarc to work properly (or alternatively save empty string to kis_paintoppresets=
, but having "All" in the file makes more sense than an empty property). ReadOnly property is not altered so "All" is not listed in "add to tag" and also is not possible to rename.