Update README.md with install instructions for openSUSE (espressif#585)

* Update README.md

* Create opensuse.md

Author: joba1

Diff for: README.md

@@ -24,6 +24,7 @@ Most of the framework is implemented. Most noticable is the missing analogWrite.
   + [Instructions for Mac](docs/arduino-ide/mac.md)
   + [Instructions for Debian/Ubuntu Linux](docs/arduino-ide/debian_ubuntu.md)
   + [Instructions for Fedora](docs/arduino-ide/fedora.md)
+  + [Instructions for openSUSE](docs/arduino-ide/opensuse.md)
 - [Using PlatformIO](docs/platformio.md)
 - [Building with make](docs/make.md)
 - [Using as ESP-IDF component](docs/esp-idf_component.md)

Diff for: docs/arduino-ide/opensuse.md

@@ -0,0 +1,16 @@
+Installation instructions for openSUSE
+======================================
+
+- Install the latest Arduino IDE from [arduino.cc](https://www.arduino.cc/en/Main/Software).
+- Open Terminal and execute the following command (copy->paste and hit enter):
+
+  ```bash
+  sudo usermod -a -G dialout $USER && \
+  sudo zypper install git python3-pip python3-pyserial && \
+  mkdir -p ~/Arduino/hardware/espressif && \
+  cd ~/Arduino/hardware/espressif && \
+  git clone https://github.com/espressif/arduino-esp32.git esp32 && \
+  cd esp32/tools/ && \
+  python get.py
+  ```
+- Restart Arduino IDE