mraa: Add types.hpp; Use types.hpp for C++ and SWIG

Signed-off-by: Petre Eftime <petre.p.eftime@intel.com>
Signed-off-by: Andrei Vasiliu <andrei.vasiliu@intel.com>
Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>

api/mraa/aio.hpp

@@ -26,6 +26,7 @@
 
 #include <stdexcept>
 #include "aio.h"
+#include "types.hpp"
 
 namespace mraa
 {
@@ -85,12 +86,12 @@ class Aio
      * Set the bit value which mraa will shift the raw reading
      * from the ADC to. I.e. 10bits
      * @param bits the bits the return from read should be i.e 10
-     * @return mraa result type
+     * @return mraa::Result type
      */
-    mraa_result_t
+    Result
     setBit(int bits)
     {
-        return mraa_aio_set_bit(m_aio, bits);
+        return (Result) mraa_aio_set_bit(m_aio, bits);
     }
     /**
      * Gets the bit value mraa is shifting the analog read to.