Merge pull request #1 from soundasleep/master

merge master
Correct Documentation.
typo
Update jsonRPCServer.php
General issues:

* Id should be incremented independently on multiple thread application.
* Alllow to set custom headers (required for some servers like bitcoind).
* Set missed header `Content-Length`
After connection headers should be cleaned up.
Allow to override loging function.
use PHP_EOL instead of \n
Allow to add and remove headers (even default).
Merge pull request #2 from armano2/master

Fix some generic issues