add night light example
add night light example

spatial-ucsb/ConceptsOfSpatialInformation,liangcun/ConceptsOfSpatialInformation,spatial-ucsb/ConceptsOfSpatialInformation,liangcun/ConceptsOfSpatialInformation,spatial-ucsb/ConceptsOfSpatialInformation,liangcun/ConceptsOfSpatialInformation