Allowed IP as alternative auth

[serk7]

Actually i'm working with a project with same name called CloudProxy (https://github.com/NoahCardoza/CloudProxy). It's to pass throw cloudflare challenge. To do that is using a chrome with pupeeter. It's starting a chrome browser passing a proxy via parameter but it doesn't accept user and password on it (https://superuser.com/questions/902620/google-chrome-proxy-settings-with-username-and-password). This is the motivation to fork it and implement an alternative way to authenticate with proxy than using user and password. I used the parameter allowed_ip from tinyproxy.

Implemented:

• Alternatrive authentication using ALLOWED_IP
• Variable environments that are using boolean now are using real boolean instead of String. Instead of using ENABLE_AWS=True now you should write ENABLE_AWS=true. And in code we are using now (if ENABLE_AWS:) instead of (if ENABLE_AWS='True')
• Check if proxy is working we are trying to load google.com throw the proxy instead of check the proxy url directly. For some strange reason proxy server response 403 HTTP forbidden when you visit is directly. Ex: http://10.12.23.3:8899 if it's using allowed_id, but it's really working as proxy. Increased timeout to 6 to let the proxy do its job.
• Added optional parameter AWS_KEY_NAME to pass throw a pairkey to login on the EC2 instance.
• Added optional parameter PROXY_STEALTH=true, default false to set proxy in stealth mode and not sending proxy headers on its requests to the sites.
• Update README.md and docs/aws.md

Since is the first time i do something on python and docker. Probably is not really optimitzed and i guess there is space to enhance. I tested it on DigitalOcean, Hetzner and AWS and it works flawless without problems atm.

I published a docker image: bubexel/cloudprroxy:latest

Thank you for your work on it!

Greetings

[claffin]

Many thanks for your contribution and sorry for the late PR review. Taking a look at this over the next day or so to merge.

[claffin]

@serk7 reviewed and tested these look good. I've added some questions about some of the changes you've made above. Let me know your thoughts otherwise I will make them myself as appreciate it's been a while since you submitted this PR.

[claffin]

Closed as stale, but will implement some features still and credit appropriately.

[serk7]

Hello Claffin, About why i added /24. I really don't remember why i did this change to be honest.

[serk7]

Btw, i saw today the email about you closing it. For some reason i didn't read the other emails when you commented. I'm really sorry for don't response in time. Now i'm working but this evening i will check my commits and i will reply your questions.