Big update here.

delayMicrosecondsHard re-written - again.
Added a serialRead example program, and added in the okLed
to the examples too.
Updated/checked some of the GPIO/PWM code.
Added in some experimental servo and tone generating code and
and example or 2.
Tweaks to the gpio command to correctly load the I2C modules too.

examples/serialRead.c

@@ -0,0 +1,31 @@
+
+/*
+ * serialRead.c:
+ *	Example program to read bytes from the Serial line
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+
+#include <wiringSerial.h>
+
+int main ()
+{
+  int fd ;
+
+  if ((fd = serialOpen ("/dev/ttyAMA0", 115200)) < 0)
+  {
+    fprintf (stderr, "Unable to open serial device: %s\n", strerror (errno)) ;
+    return 1 ;
+  }
+
+// Loop, getting and printing characters
+
+  for (;;)
+  {
+    putchar (serialGetchar (fd)) ;
+    fflush (stdout) ;
+  }
+}