Implemented proxy spec and useragent spoofing

README

@@ -127,6 +127,23 @@ On success, tiipost.tcl will output a message that starts with "Success", in
 case of an error the line will start with "Error". The server-side description
 will follow this success or error status.
 
+HTTP client configuration
+-------------------------
+For both fetching and posting, you can configure several values in the config
+file (config.txt in the script directory, the example is included in the repo)
+that will allow you to set HTTP proxy and override the user agent. As of now,
+the file is a Tcl dictionary (`key "value"`) and has the following fields:
+
+* useragent: the user agent string to set for all HTTP requests
+* proxyhost: the HTTP proxy hostname to use (if empty or omitted, the scripts
+  will connect directly)
+* proxyport: the HTTP port to use on the proxy (only effective if proxyhost is
+  set to a non-empty string)
+
+Any of the fields can be omitted, as well as the file itself.
+You can also use torsocks with any script invocation in order to fully cloak
+your originating IP address.
+
 Message database format
 -----------------------
 The tiidb format is based upon the official ii/IDEC developer recommendations