[STSK28] HTTP Proxy Framework Configuration Option

[vexance]

Add an additional framework configuration option for HTTP_PROXY that can be leveraged by modules to send web traffic through a web proxy such as Burp Suite.

Also, perhaps consider a parent-class module method to perform a request while always adhering to the framework HTTP_PROXY config. Then modules could use self.http_request(args) without needing to get/check/specify the HTTP_PROXY.

[vexance]

Testing a quick PoC within a module's options makes it appear that something along the lines of this will work:

        self._options.add_string('HTTP_PROXY', 'Web proxy (schema://host:port) to use for HTTP(S) requests (e.g., \'http://127.0.0.1:8080\')', False)
...
        proxy = self.get_opt('HTTP_PROXY')
        if proxy not in ['', None]:
            if proxy.startswith('http'):
                self.proxies = {
                    'http': proxy,
                    'https': proxy
                }

And then performing a request via:

res = requests.request(method, endpoint, headers=req.http_headers, verify=ssl_verification, auth=sig, json=req.http_body, proxies=self.proxies)

[vexance]

Implemented via #29 - closing