Feature: Add regex input field to inlude proxy for certian hosts

[divyam234]

Aria2c doesn't support proxy hosts filter but it can easily be done through ui which asks for regex to include certain hosts for http proxy.

https://github.com/divyam234/AriaNg/commit/4201ec0aa4302ec5f4c67702465fa80663ccc27d

I have added this in my fork

[mayswind]

I think you can use one AriaNg option to match different http urls and use a specified proxy server, similar to the following

^https?:\/\/one\.domain\.com\/|proxy1.com:8000
^https?:\/\/another\.domain\.com\/|proxy2.com:8000

For urls using the domain "one.domain.com", the download task would use proxy1.com:8000 as proxy server.

Welcome to submit a pull request!