LP#1301510 Align element name with Fixed Field type

We depend on the field name in the XUL to line up the fixed field
value maps in the database with the appropriate context menus. ELvl
was not capitalized the same in all required spots, causing the
context menu to render but be ineffective.

Signed-off-by: Mike Rylander <mrylander@gmail.com>
Signed-off-by: Remington Steed <rjs7@calvin.edu>
Signed-off-by: Dan Wells <dbw2@calvin.edu>