Add docs to IWrenchable

src/main/java/com/raoulvdberge/refinedstorage/api/util/IWrenchable.java

@@ -2,8 +2,22 @@ package com.raoulvdberge.refinedstorage.api.util;
 
 import net.minecraft.nbt.NBTTagCompound;
 
+/**
+ * Implement this on a tile that is wrenchable.
+ */
 public interface IWrenchable {
+    /**
+     * Writes the configuration of this tile to the wrench.
+     *
+     * @param tag the tag to write to
+     * @return the written tag
+     */
     NBTTagCompound writeConfiguration(NBTTagCompound tag);
 
+    /**
+     * Reads the configurration of this tile from the wrench.
+     *
+     * @param tag the tag to read
+     */
     void readConfiguration(NBTTagCompound tag);
 }