3.6 - Helper functions needed

[mervb]

Need some helper functions fo fetch the label from the array:

EG
get_property_commercial_category
has a label function
epl_listing_meta_property_category_value

These need similar functions:
epl_get_property_authority_opts
epl_get_property_exclusivity_opts
epl_get_property_com_authority_opts
epl_get_property_area_unit_opts
epl_get_property_rent_period_opts
epl_get_property_com_listing_type_opts
epl_get_property_com_tenancy_opts
epl_get_property_com_property_extent_opts