WSGI_PATH check multiple levels to find wsgi.py

In addition would be great if your base image support multiple folder depths. wsgi.py is not always located one level deep. Especially if you have multiple django apps, you may want a command such as:

WSGI_PATH=`find /var/app | egrep 'wsgi.py'`

This would allow more projects based on this docker image, using a project structure such as:

/backend
/polls
/mysite
wysgi.py
/frontend
gulpfile.js
package.json
/src

Thanks!

检查当前设置 WSGI_PATH 的基础镜像启动配置，然后复现 issue 中所示的嵌套 /backend/mysite/wsgi.py 布局。当镜像能够在多个文件夹深度中定位 wsgi.py，同时保留对现有布局的支持时，此更改即完成。

由索引模型根据 Issue 内容生成。