Expose BlockState string representation (#2425)

* Expose BlockState string representation

* Clarify BlockState#asString javadoc

Author: Yeregorix

src/main/java/org/spongepowered/api/block/BlockState.java

@@ -157,6 +157,14 @@ default BlockState mirror(final Supplier<? extends Mirror> mirror) {
         return this.mirror(mirror.get());
     }
 
+    /**
+     * Gets a string representation of this block state, including the block type and the properties.
+     * Do not confuse with {@link #toString} which is implementation specific.
+     *
+     * @return A string representation of this block state.
+     */
+    String asString();
+
     /**
      * An {@link org.spongepowered.api.data.DataHolderBuilder.Immutable} for a {@link BlockState}. Just like the
      * {@link org.spongepowered.api.data.DataHolderBuilder.Immutable}, the {@link Value}s passed in to