Make sorting in connector table not do so based on strings but numbers.
Add section index column to connector table.
Section index in treenode table is not sortable because it is computed
after the sorting is done. Sorting by Z has the same effect so won't fix.
Add forgotten update to WindowMaker.js to add the new section index column
to the connector table.
Add 'var' to att, otherwise it's a global variable.
Add menu item "Give neuron to user..." to popup of Object Tree.

This function allows a user to give neurons that he owns to other users.
The user_id of the neuron and its skeletons is changed to that of the
target user, but all nodes remain the same.