[Build] Fix passing local natives to the example

resolves #48

example/build.gradle

@@ -8,6 +8,9 @@ repositories {
 
 application {
     mainClass = 'Main'
+    if (libPath) {
+        applicationDefaultJvmArgs = ["-Dimgui.library.path=$libPath"]
+    }
 }
 
 dependencies {