Added a GPIO to power on/off for external I2C sensor(s) (with LEDs)

Dependencies:   UniGraphic mbed vt100

18-Jun-2018 外部センサの電源オン・オフ機能は下位互換の為に無効になっていました。 この版で再度有効にしました。

Revision:
0:846e2321c637
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/afLib/afErrors.h	Fri Apr 13 04:19:23 2018 +0000
@@ -0,0 +1,28 @@
+/**
+ * Copyright 2015 Afero, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef AF_ERRORS_H__
+#define AF_ERRORS_H__
+
+#define afSUCCESS                    0    // Operation completed successfully
+#define afERROR_NO_SUCH_ATTRIBUTE   -1    // Request was made for unknown attribute id
+#define afERROR_BUSY                -2    // Request already in progress, try again
+#define afERROR_INVALID_COMMAND     -3    // Command could not be parsed
+#define afERROR_QUEUE_OVERFLOW      -4    // Queue is full
+#define afERROR_QUEUE_UNDERFLOW     -5    // Queue is empty
+#define afERROR_INVALID_PARAM       -6    // Bad input parameter
+
+#endif // AF_ERRORS_H__
\ No newline at end of file