Enable opening org note files directly from pdf

When in a pdf buffer, if interleave is not yet enabled, hitting i will open its corresponding notes org file.
The notes file is searched in the order the directory names are listed in the interleave--org-notes-dir-list custom variable. The first successfully matched org file is opened. If a directory name is ".", the search will also happen in the same directory as the pdf file.
If the notes file is not found in any of the directories in the list, it is created in the FIRST directory from the list.
The default value of this list is: '("~/org/interleave_notes" "."). So by default, if for a pdf file "/path/to/filexyz.pdf" its notes file does not exist, then its notes org file will be created as "~/org/interleave_notes/filexyz.org".

rudolfochrist / interleave