This week, two projects revolving around legendary 20th century rock figures hit streaming, though the subjects, and the projects, couldn’t be more different. First up, the documentary “Poly Styrene: I Am a Cliche” will be in theaters nationwide Wednesday for a one night only big screen event before becoming available to rent digitally on Friday. The pioneering punk princess Poly Styrene, the lead singer of the British punk band X-Ray Spex, was the first woman of color to front a successful rock band in the U.K. Her distinctive voice and delightfully daffy DIY fashion, along with her insightfu…