Add Ota and mdns (#257)

* Add Sketch Update Library

* Add MDNS Library

* Add Arduino OTA Library

* add missing library file

* Add library files for Update

* Add missing headers

* fix ota command

* Add espota binary

* remove bad example

* PlatformIO does not auto forward declare methods like Arduino Builder

tools/sdk/include/bootloader_support/esp_efuse.h

@@ -0,0 +1,56 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// 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 _ESP_EFUSE_H
+#define _ESP_EFUSE_H
+
+#include "soc/efuse_reg.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* @brief Permanently update values written to the efuse write registers
+ *
+ * After updating EFUSE_BLKx_WDATAx_REG registers with new values to
+ * write, call this function to permanently write them to efuse.
+ *
+ * @note Setting bits in efuse is permanent, they cannot be unset.
+ *
+ * @note Due to this restriction you don't need to copy values to
+ * Efuse write registers from the matching read registers, bits which
+ * are set in the read register but unset in the matching write
+ * register will be unchanged when new values are burned.
+ *
+ * @note This function is not threadsafe, if calling code updates
+ * efuse values from multiple tasks then this is caller's
+ * responsibility to serialise.
+ *
+ * After burning new efuses, the read registers are updated to match
+ * the new efuse values.
+ */
+void esp_efuse_burn_new_values(void);
+
+/* @brief Reset efuse write registers
+ *
+ * Efuse write registers are written to zero, to negate
+ * any changes that have been staged here.
+ */
+void esp_efuse_reset(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __ESP_EFUSE_H */
+