Fix errors in composer 2.0 with uppercase letters in the package names

Author: markcameron

composer.json

@@ -12,13 +12,13 @@
   "require": {
     "php": ">=5.4.0",
     "tedivm/jshrink": "~1.0",
-    "natxet/CssMin": "3.*",
+    "natxet/cssmin": "3.*",
     "illuminate/filesystem": "~5.0|^6|^7",
     "illuminate/support": "~5.0|^6|^7"
   },
   "require-dev": {
     "phpspec/phpspec": "2.0.0",
-    "mikey179/vfsStream": "1.2.*"
+    "mikey179/vfsstream": "1.2.*"
   },
   "autoload": {
     "psr-4": {