Prado-RPC repo - move RPC (XML and JSON) to separate repo (RPC is legacy)

[belisoful]

RPC Client is in Util rather than IO. It should be in IO.
There is a larger issue: XML-RPC extension was removed in PHP 8 disabling the xml-rpc classes in Prado.
and XML-RPC was superseded by JSON-RPC in 2010 (hence the removal of xml-rpc from PHP 8).
As such, a new CODEC class is required to fill in the MIA xml-rpc extension.

RPC is superseded by REST (#1155).

It is proposed to move RPC out of PRADO into its own repo, like currently for sqlmap

[belisoful]

Completed with new repo https://github.com/pradosoft/prado-rpc
RPC Client and Server Services removed from PRADO in #1229.

Migration Guide: https://github.com/pradosoft/prado-rpc/blob/main/docs/migration.md

Changes:

• Client classes moved namespace
• The transport is now the PRADO HTTP client
• XML-RPC no longer needs the xmlrpc extension
• TRpcClientTypesEnumerable removed for an auto-detector.
• Request and response exceptions.