Add IML input option to NSHM Hazard Tool Disaggregation

New components for disagg control panel:

• toggle: IML or Return Period; action: enable/disable the input fields below as appropriate
• Input field with "IML (geomean, g)" placed below current 'Return Period' fields
• It's conceivable that the two rows of inputs could start with radio buttons that just enables/disables one input option or the other; the separate toggle and text wouldn't be needed

Based on which input is selected, the appropriate disagg service endpoint should be used.

Also, because the "Hazard Curves" (static and dynamic) tools have a "Scale to Max Direction" option, consider adding a "Max Direction?" checkbox next to the IML input box.