classes/Plugin: remove dbh & host fields; set init() and about() as abstract methods.

classes/plugin.php

@@ -1,19 +1,11 @@
 <?php
-class Plugin {
-	private $dbh;
-	private $host;
-
+abstract class Plugin {
 	const API_VERSION_COMPAT = 1;
 
-	function init($host) {
-		$this->dbh = $host->get_dbh();
-		$this->host = $host;
-	}
+	abstract function init($host);
 
-	function about() {
-		// version, name, description, author, is_system
-		return array(1.0, "plugin", "No description", "No author", false);
-	}
+	abstract function about();
+	// return array(1.0, "plugin", "No description", "No author", false);
 
 	function flags() {
 		/* associative array, possible keys: