ptig - support dir/ls with no parameters

Assumes root of (first) note directory.

puren_tonbo/tools/ptig.py

@@ -286,12 +286,14 @@ def do_ls(self, line=None):
         # TODO show file size and timestamps
         line = self.validate_result_id(line)
         if line is None:
-            return
+            #return
+            # assume current directory (for now, that means root directory)
+            line = '.'
 
         sub_dir = os.path.dirname(line)  # similar open to opendir - but for directory listings, i.e. can NOT ls/dir a single file (future TODO?)
         print('DEBUG sub_dir %s' % sub_dir)
         note_encoding = self.pt_config['codec']
-        note_root = self.paths_to_search[0]  # TODO just pick the first one, ignore everthing else
+        note_root = self.paths_to_search[0]  # FIXME handle multiple note dirs, read and new do. TODO just pick the first one, ignore everthing else
         notes = puren_tonbo.FileSystemNotes(note_root, note_encoding)
         # TODO handle; puren_tonbo.PurenTonboIO: outside of note tree root? no need, handled by validate_result_id()
         # FIXME/TODO results list with numbers?