当把Flutter环境变量配置之后，打开cmd输入：flutter
出现如下错误：
'MySQL' is not recognized as an internal or external command,
operable program or batch file.
'MySQL' is not recognized as an internal or external command,
operable program or batch file.
'where' is not recognized as an internal or external command,
operable program or batch file.
Error: Unable to find git in your PATH.
与MySQL有啥关系？？？
解决方法：
从系统环境变量中移除环境变量中的以下两个：
C:\Program Files (x86)\MySQL\MySQL Fabric 1.5 & MySQL Utilities 1.5\;
C:\Program Files (x86)\MySQL\MySQL Fabric 1.5 & MySQL Utilities 1.5\Doctrine extensions for PHP\;
