Graphics and SFX Changes

* Adds Background parallax images (not exactly parallax since we have a fixed camera)
* Adds SFX
* Fixes Pickable collisions and SFX playback

sfx/found_item.wav.import

@@ -0,0 +1,21 @@
+[remap]
+
+importer="wav"
+type="AudioStreamSample"
+path="res://.import/found_item.wav-018b3bdc3b80db7e8e7981fb2514df67.sample"
+
+[deps]
+
+source_file="res://sfx/found_item.wav"
+dest_files=[ "res://.import/found_item.wav-018b3bdc3b80db7e8e7981fb2514df67.sample" ]
+
+[params]
+
+force/8_bit=false
+force/mono=false
+force/max_rate=false
+force/max_rate_hz=44100
+edit/trim=false
+edit/normalize=false
+edit/loop=false
+compress/mode=0