- First do not write the protocol-version (and therefore don't read it either
nor compare it to the current one). This file does not depend on the protocol
version.
- Secondly when reading an unknown identifier, simply print a message on stderr
for debugging/reference, but ignore it up to the next closing parenthese.
- Finally do not use the file-version as a terminal error as well. When we read
a shortcutsrc with the wrong version, we still try to read it as best as we
can. There might be issues, but it's better than fully dropping the whole list
of shortcuts as it's a pretty important file (people might have spent a lot of
time tweaking their shortcuts!).