Bug#444175: Further notes

[David Purdy]

A few more notes:

Other cells with 1-character numeric contents ('1', '2', etc) are editable.

I'm guessing that there is logic in gtk which checks the liststore 'int' cell
contents, but there is a bug where the 'int' values are used in a boolean
condition, and the '0' value causes the necessary logic (to make the cell
editable) to be skipped.

Either that or '0' is somehow a magic value which causes cells to become
uneditable.