Add initial commissioning commands support to the NCP (#1393)

* Add initial commissioning commands support to the NCP

* Make GetPropertyHandler_THREAD_COMMISSIONER_ENABLED send true only if commissioner active, move commissioner state enum to oepnthread/types.h

* Use enum to return commissioner state, make spinel property return true only if Commissioner State Active

* Fix spinel documentation

include/openthread/commissioner.h

@@ -224,6 +224,18 @@ OTAPI ThreadError OTCALL otCommissionerSendMgmtSet(otInstance *, const otCommiss
  */
 OTAPI uint16_t OTCALL otCommissionerGetSessionId(otInstance *);
 
+/**
+ * This function returns the Commissioner State.
+ *
+ * @param[in]  aInstance  A pointer to an OpenThread instance.
+ *
+ * @retval kCommissionerStateDisabled    Commissioner disabled.
+ * @retval kCommissionerStatePetition    Becoming the commissioner.
+ * @retval kCommissionerStateActive      Commissioner enabled.
+ *
+ */
+OTAPI otCommissionerState OTCALL otCommissionerGetState(otInstance *);
+
 /**
  * This method generates PSKc.
  *

include/openthread/types.h

@@ -282,6 +282,18 @@ enum
     OT_SECURITY_POLICY_BEACONS                = 1 << 3,  ///< Beacons enabled
 };
 
+/**
+* This enumeration defines the Commissioner State.
+*
+*/
+typedef enum otCommissionerState
+{
+
+    kCommissionerStateDisabled = 0,
+    kCommissionerStatePetition = 1,
+    kCommissionerStateActive = 2,
+} otCommissionerState;
+
 /**
   * This type represents Channel Mask Page 0.
   *