add hemtt support, major refactor

- no longer supports server events
- can now more easily build using hemtt
- extension vastly improved in both structure and functionality
- tested on listen server
- includes schema change

addons/main/functions/fn_callbackHandler.sqf

@@ -0,0 +1,24 @@
+addMissionEventHandler ["ExtensionCallback", {
+	params ["_name", "_function", "_data"];
+	if !(_name isEqualTo "AttendanceTracker") exitWith {};
+
+	if (ATDebug && _function isNotEqualTo ":LOG:") then {
+		diag_log format ["Raw callback: %1 _ %2", _function, _data];
+	};
+
+	_dataArr = parseSimpleArray _data;
+	if (count _dataArr < 1) exitWith {};
+
+	switch (_function) do {
+		case ":LOG:": {
+			diag_log formatText[
+				"[Attendance Tracker] %1",
+				_dataArr select 0
+			];
+		};
+		default {
+			[format["%1", _dataArr]] call attendanceTracker_fnc_log;
+		};
+	};
+	true;
+}];