Changes

Two 90mm HMDs, at a resolution of 1080 x 1200 per eye, makes each display 455.63 PPI<ref>https://www.ifixit.com/Teardown/Oculus+Rift+CV1+Teardown/60612#s126626</ref><ref>http://arstechnica.com/gaming/2016/03/ifixit-digs-into-oculus-rifts-461ppi-oled-display-custom-lenses/</ref>