Update esptool on mac and windows and revert linux to use python

Author: me-no-dev

README.md

@@ -47,6 +47,9 @@ Most of the framework is implemented. Most noticable is the missing analogWrite.
   ```bash
   sudo usermod -a -G dialout $USER && \
   sudo apt-get install git && \
+  wget https://bootstrap.pypa.io/get-pip.py && \
+  sudo python get-pip.py && \
+  sudo pip install pyserial && \
   mkdir -p ~/Arduino/hardware/espressif && \
   cd ~/Arduino/hardware/espressif && \
   git clone https://github.com/espressif/arduino-esp32.git esp32 && \