Add JMU_Items to ListMaker

Users can now add items of their own (these are called JMU_Items after the table name, which distinguishes them from R2 items) and then add those to lists. Still to be done:

1. the Delete Item does not work yet / again for items from lists. (@#$%) Deleting lists works fine so I should start there.
2. So Ranking might be something to tackle, next.
3. Then the user login.