Variables starting with `r' in linuxdoom

• record src/r_defs.h:96
• redundant src/i_video.c:589
• refresh src/changelog:97
• release src/readme.book:4
• reloadlump src/w_wad.c:137
• reloadname src/w_wad.c:138
• rendered src/m_menu.c:1737
• Retrieval src/r_data.c:670
• right src/am_map.c:157
• rndindex src/m_random.c:53
• rotation src/r_defs.h:414