Add optional module support

.travis.yml

@@ -5,6 +5,8 @@ php:
    - 5.6
    - nightly
 
-before_script: php build.php
+before_script:
+   - php build.php
+   - ls modules/*.php | xargs -n 1 php -l
 
 script: php -l build/index.php

build.php

@@ -22,6 +22,11 @@ $module_index = [];
 function register_module($settings)
 {
 	global $module_index;
+	
+	// If the optional flag isn't set, then we should set it to false.
+	if(!isset($settings["optional"]) || !is_bool($settings["optional"]))
+		$settings["optional"] = false;
+	
 	$newmodule = [
 		"name" => $settings["name"],
 		"version" => $settings["version"],

pack.php

@@ -10,6 +10,10 @@ $module_index = json_decode(file_get_contents("module_index.json"));
 $module_list = [];
 foreach($module_index as $module)
 {
+	// If the module is optional, the module's id isn't present in the command line arguments, and the special '*' module id wasn't passed in, skip it
+	if($module->optional &&
+	   strrpos(implode(" ", $argv), $module->id) === false &&
+	   !in_array("*", $argv)) continue;
 	$module_list[] = $module->id;
 }