rotaryencoder: Adding doxygen comments and image from seeed wiki

Signed-off-by: John Van Drasek <john.r.van.drasek@intel.com>

src/rotaryencoder/rotaryencoder.h

@@ -31,20 +31,34 @@
 namespace upm {
 
 /**
+ * @brief Grove Rotary Encoder library
+ * @defgroup rotaryencoder libupm-rotaryencoder
+ * @ingroup seeed gpio other
+ */
+/**
+ * @library libupm-rotaryencoder
+ * @sensor rotaryencoder
+ * @comname Grove Rotary Encoder
+ * @type other
+ * @man seeed
+ * @web http://www.seeedstudio.com/wiki/Grove_-_Encoder
+ * @con gpio
+ * @kit gsk
+ *
  * @brief C++ API for the Grove Rotary Encoder
  * 
  * UPM module for the Grove Rotary Encoder.  A Rotary Encoder
  * encodes a rotation signal into electronic pulses that can be used
  * to measure rotation and direction.  It is useful in cases where a
  * rotary knob is required, but using a potentiometer is not
-   * desireable.  A rotary encoder can turn a full 360 degrees+
+ * desirable.  A rotary encoder can turn a full 360 degrees+
  * without a stop and does not place a resistive load on the
  * circuit, as is the case with a potentiometer.
  *
  * This module maintains a position that is incremented or
  * decremented according to the rotation on the encoder.
  *
-   * @ingroup gpio 
+ * @image html rotaryencoder.jpg
  * @snippet rotaryencoder.cxx Interesting
  */
   class RotaryEncoder {