Fixed version info in README.md

Author: D4mianWayne

README.md

@@ -84,7 +84,7 @@ ______ _  __  ________
 | |/ /| | | | | | |\ \ (_| | |_| \__ \
 |___/ |_|_| |_| \_| \_\__,_|\__, |___/
                              __/ |
-                            |___/      v1.5 Omicron
+                            |___/      v1.6 Pi
 
 usage: diffrays [-h] {diff,server,autodiff} ...