Fixed macro so it mentions M6

README.md

@@ -259,7 +259,7 @@ buildscript {
         mavenLocal()
     }
     dependencies {
-        classpath("org.springframework.boot:spring-boot-gradle-plugin:0.5.0.M4")
+        classpath("org.springframework.boot:spring-boot-gradle-plugin:0.5.0.M6")
     }
 }
 ```