The Mattatuck Museum in Waterbury, which was extensively renovated and reinvigorated a few years ago, has two sharp modern exhibits on view for a few more weeks. “Andy Warhol: Endangered Species” is a series of colorful prints the pop artist did for a charitable cause in 1983. The prints are augmented for the exhibit with “tactile” renderings for the sight-impaired (basically Warhol’s strong .