Changed required modules

* Added dependency for ext-mysqli
* Added dependency for simplesamlphp/simplesamlphp
* Bumped required version of cesnet/simplesamlphp-module-perun

Author: vyskocilpavel

composer.json

@@ -13,6 +13,8 @@
   ],
   "require": {
     "php": ">=5.4.0",
-    "cesnet/simplesamlphp-module-perun" : ">=1.0.0"
+    "cesnet/simplesamlphp-module-perun" : "~3.0",
+    "simplesamlphp/simplesamlphp": "~1.17",
+    "ext-mysqli": "*"
   }
 }