document the daemon classes

Zotlabs/Daemon/README.md

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+Daemon (background) Processes
+=============================
+
+
+This directory provides background tasks which are executed by a 
+command-line process and detached from normal web processing.
+
+Background tasks are invoked by calling
+
+
+	Zotlabs\Daemon\Master::Summon([ $cmd, $arg1, $argn... ]); 
+
+The Master class loads the desired command file and passes the arguments.
+
+
+To create a background task 'Foo' use the following template.
+
+	<?php
+	
+	namespace Zotlabs\Daemon;
+	
+	class Foo {
+	
+		static public function run($argc,$argv) {
+			// do something
+		}
+	}
+
+
+The Master class "summons" the command by creating an executable script
+from the provided arguments, then it invokes "Release" to execute the script
+detached from web processing. This process calls the static::run() function
+with any command line arguments using the traditional argc, argv format. 
+
+Please note: These are *real* $argc, $argv variables passed from the command
+line, and not the parsed argc() and argv() functions/variables which were 
+obtained from parsing path components of the request URL by web processes.
+
+Background processes do not emit displayable output except through logs. They 
+should also not make any assumptions about their HTML and web environment 
+(as they do not have a web environment), particularly with respect to global
+variables such as $_SERVER, $_REQUEST, $_GET, $_POST, $_COOKIES, and $_SESSION.
+