Make half-length swalls proper length.

In the process of updating COPYING, found an inaccuracy from the upgrade to hunter's bow and corrected it too.

COPYING.rtro

@@ -99,6 +99,7 @@ mb_lavawell: Referenced from retro lava well, which is derived from retro well.
 mbgreenmarble, mblightmagentamarble, mbmarble, mbpinkmarble: Derived from their respective marble images, all of which are derived from the white marble image. License unknown.
 mbwoodfloor, mbwoodfloor2: Derived from their respective woodfloor images. License unknown.
 mbblackmarble: Derived from retro black marble image. License unknown.
+swall_1_half, swall_2_half, swall_4_half, swall_8_half: Derived from respective retro swall images. License unknown.
 
 Original images with known licenses:
 jade_coin: Created by SilverNexus. Licensed as CC-0.
@@ -165,7 +166,6 @@ weapon/bow/arrow: All 8 directional facings are colorized versions of images in
 weapon/bow/bow: Colorized, but otherwise appears to be identical.
 - Derivatives of bow:
 -- weapon/bow/compositebow
--- weapon/bow/huntersbow
 weapon/club/club: Colorized, but otherwise appears to be identical.
 weapon/mace/mace_1: Colorized, but otherwise appears to be identical.
 weapon/sword/sword_1: Colorized, but otherwise appears to be identical.

ChangeLog.rtro

@@ -1,6 +1,8 @@
 ------------------------
 Changes for top of trunk
 ------------------------
+	* wall/swall/swall_[1248]_half.rtro.111.png: Modify existing images to be half-length walls.
+
 2023-08-15 Daniel Hawkins
 	* light/torch_unlit.rtro.111.png: Replace what appeared to be a classic or base unlit torch
 	    with one from 1.0.0. Now follows XPM palette.