Add authentication and upload options

Author: ivankravets

doc/platformio.md

@@ -53,17 +53,33 @@ platformio run --target upload
 
 There are 2 options:
 
-1. Directly specify `--upoad-port` in command line
+- Directly specify `--upoad-port` in command line
 ```bash
 platformio run --target upload --upload-port IP_ADDRESS_HERE
 ```
-2. Specify [upload_port](http://docs.platformio.org/en/latest/projectconf.html#upload-port) option in `platformio.ini`
+- Specify [upload_port](http://docs.platformio.org/en/latest/projectconf.html#upload-port) option in `platformio.ini`
 ```ini
 [env:***]
 ...
 upload_port = IP_ADDRESS_HERE
 ```
 
+### Authentication and upload options
+
+You can pass additional options/flags to OTA uploader using [upload_flags](http://docs.platformio.org/en/latest/projectconf.html#upload-flags)  option in `platformio.ini`
+```ini
+[env:***]
+upload_flags = --port=8266
+```
+
+Availalbe flags
+- `--port=ESP_PORT` ESP8266 ota Port. Default 8266
+- `--auth=AUTH` Set authentication password
+- `--spiffs` Use this option to transmit a SPIFFS image and do not flash the module
+
+For the full list with availalbe options please run this command `~/.platformio/packages/framework-arduinoespressif/tools/espota.py -h`.
+
+
 ## IDE Integration
 In addition, PlatformIO [can be integrated into the popular IDEs](http://docs.platformio.org/en/latest/ide.html). For example, initialise project for Espressif ESP8266 ESP-01 board and Eclipse IDE
 ```