windows: Update pre-compiled MSYS2 environment

* Latest MSYS2 packages
* Uses Python 3 now (no more Python 2 in MSYS2)

This pre-compiled package is not suitable of ESP-IDF v4.x

docs/en/get-started/windows-setup.rst

@@ -14,7 +14,7 @@ Toolchain Setup
 
 The quick setup is to download the Windows all-in-one toolchain & MSYS2 zip file from dl.espressif.com:
 
-https://dl.espressif.com/dl/esp32_win32_msys2_environment_and_gcc5_toolchain-20191220.zip
+https://dl.espressif.com/dl/esp32_win32_msys2_environment_and_toolchain_idf3-20200601.zip
 
 Unzip the zip file to ``C:\`` (or some other location, but this guide assumes ``C:\``) and it will create an ``msys32`` directory with a pre-prepared environment.
 

docs/zh_CN/get-started/windows-setup.rst

@@ -15,7 +15,7 @@ Windows 没有内置的 "make" 环境，因此如果要安装工具链，你需
 
 快速设置的方法是从 dl.espressif.com 下载集成在一起的工具链和 MSYS2 压缩文件：
 
-https://dl.espressif.com/dl/esp32_win32_msys2_environment_and_toolchain-20181001.zip
+https://dl.espressif.com/dl/esp32_win32_msys2_environment_and_toolchain_idf3-20200601.zip
 
 将 zip 压缩文件解压到 ``C:\`` (或其它路径，这里假设是 ``C:\``)，它会使用预先准备的环境创建一个 ``msys32`` 目录。
 

tools/windows/windows_install_prerequisites.sh

@@ -34,7 +34,7 @@ set -e
 pacman --noconfirm -Syu # This step may require the terminal to be closed and restarted
 
 pacman --noconfirm -S --needed gettext-devel gcc git make ncurses-devel flex bison gperf vim \
-       mingw-w64-i686-python2-pip mingw-w64-i686-python2-cryptography unzip winpty
+       mingw-w64-i686-python-pip mingw-w64-i686-python-cryptography unzip winpty
 
 # if IDF_PATH is set, install requirements now as well
 if [ -n "$IDF_PATH" ]; then