Add http proxy config

nitter.example.conf

@@ -23,6 +23,8 @@ redisMaxConnections = 30
 hmacKey = "secretkey" # random key for cryptographic signing of video urls
 base64Media = false # use base64 encoding for proxied media urls
 enableRSS = true  # set this to false to disable RSS feeds
+proxy = "" # proxy type http/https
+proxyAuth = ""
 tokenCount = 10
 # minimum amount of usable tokens. tokens are used to authorize API requests,
 # but they expire after ~1 hour, and have a limit of 187 requests.