move minecraft home path retrieval to separate util class

src/main/java/com/falsepattern/lib/util/FileUtil.java

@@ -0,0 +1,13 @@
+package com.falsepattern.lib.util;
+
+import com.falsepattern.lib.StableAPI;
+import net.minecraft.launchwrapper.Launch;
+
+import java.io.File;
+
+@StableAPI(since = "0.8.2")
+public class FileUtil {
+    public static File getMinecraftHome() {
+        return Launch.minecraftHome == null ? new File(".") : Launch.minecraftHome;
+    }
+}