Opens zettel by linked value, most often a direct path link, but will
also look through the root dir to find a(n exactly) matching basename to
open.
If nothing is found in the root dir will open a new file to write with
the corresponding name. Careful, if the reference is a full path
definition, and the file does not exist, it will still open the
corresponding file at the correct location but when attempting to save
will generally complain if parts of the path are missing. They have to
be created manually or in some other place, this is outside the scope of
this plugin.