update TODO

TODO.txt

@@ -1,4 +1,5 @@
 - if one of the previously loaded files doesn't load/exist, still 2 tables are displayed; afterwards second opened file isn't restored on next launch
+- row numbers not updated after paste
 
 MarcoNecroX:
 3) Save user's table parameters - for example; everytime I load the program I have the key column covering all screen, and string column is not visible so I have to fix the columns everytime I open the program.
@@ -11,3 +12,7 @@ MarcoNecroX:
 - warn if start/end non-alphadigit characters don't match
 - display non-printable characters
 - highlight current row number
+
+- add new "comment" column that will be saved to "extended txt" format
+- xml/json
+- formats for machine consumption (e.g. xml/json) can contain parsed color info: text range + color