Changed the build system to drop I2C for now. Seems to cause too many issues

on non Raspbian systems (and even on some Raspbian systems it would appear ):

fixed a timing issue on softTone
fixed some issues in wiringPisetup introduced when optimising the mmap calls.

wiringPi/softTone.c

@@ -59,7 +59,9 @@ static PI_THREAD (softToneThread)
   for (;;)
   {
     frewq = frewqs [pin] ;
-    if (frewq != 0)
+    if (frewq == 0)
+      delay (1) ;
+    else
     {
       halfPeriod = 500000 / frewq ;