Gradle: Add decompile task to projects (#1273)

* Gradle: Add decompile task to projects

* add ff as dependency rather than adding ti in buildsrc

* smh smh smh smh smh

* Add ff version in buildsrc build file

This doesn't work in ext as it officially isn't part of the project

* Add missing ''s

injected-client/build.gradle

@@ -44,3 +44,6 @@ classes.doLast() {
     File f = file("build/classes/java/main/Placeholder.class")
     f.delete()
 }
+
+// tasks.build.dependsOn(tasks.decompile)
+// this is just here to show how this could be used