Composer: sort packages, set platform version

* Upgrade mrclay/props-dic
* Also support existing version

composer.json

@@ -1,7 +1,7 @@
 {
 	"name": "mrclay/minify",
 	"type": "library",
-	"description": "Minify is a PHP5 app that helps you follow several rules for client-side performance. It combines multiple CSS or Javascript files, removes unnecessary whitespace and comments, and serves them with gzip encoding and optimal client-side cache headers",
+	"description": "Minify is a PHP app that helps you follow several rules for client-side performance. It combines multiple CSS or Javascript files, removes unnecessary whitespace and comments, and serves them with gzip encoding and optimal client-side cache headers",
 	"homepage": "https://github.com/mrclay/minify",
 	"license": "BSD-3-Clause",
 	"authors": [
@@ -22,15 +22,21 @@
 	"autoload-dev": {
 		"psr-4": {"Minify\\Test\\": "tests/"}
 	},
+	"config": {
+		"platform": {
+			"php": "5.3.29"
+		},
+		"sort-packages": true
+	},
 	"require": {
+		"php": "^5.3.0 || ^7.0",
 		"ext-pcre": "*",
 		"intervention/httpauth": "~2.0",
+		"marcusschwarz/lesserphp": "~0.5.1",
 		"monolog/monolog": "~1.1|~2.0",
 		"mrclay/jsmin-php": "~2",
-		"mrclay/props-dic": "^2.2",
-		"php": "^5.3.0 || ^7.0",
-		"tubalmartin/cssmin": "~4",
-		"marcusschwarz/lesserphp": "~0.5.1"
+		"mrclay/props-dic": "^2.2|^3.0",
+		"tubalmartin/cssmin": "~4"
 	},
 	"require-dev": {
 		"firephp/firephp-core": "~0.4.0",