Strollers along the corner of South Pine and Spring streets in Nevada City were greeted Sunday with an unusual sight: two broken halves of Nevada City Marketplace’s business sign leaned against one another with R.I.P. painted on them. This caused some confusion. Was the store closed? Was this vandalism? “That was my husband’s art project. A protest with the city for not getting the sign approved,” said Caroline Szekely, who operated Nevada City Marketplace until Friday. Szekely and her husband, Rick, opened just before the 2011 Wild and Scenic Environmental Film Festival. They closed their doors at Nevada City Marketplace …