Remove meaningless keys caught by wmltest. (no, it's not in the repo yet)

data/game_config.cfg

@@ -36,7 +36,6 @@
     logo_x=160
     logo_y=40
     tip_x=100
-    tip_y=500
     tip_width=495
     tip_padding=4
 #else
@@ -47,8 +46,6 @@
     logo_x=85
     logo_y=20
     tip_x=30
-    #does this option do anything at all?!?
-    tip_y=500
     tip_width=620
     tip_padding=20
 #else
@@ -58,7 +55,6 @@
     logo_x=292
     logo_y=120
     tip_x=100
-    tip_y=500
     tip_width=495
     tip_padding=20
 #endif
@@ -66,10 +62,6 @@
 
     lobby_refresh=2000
 
-    map_image="maps/wesnoth.png"
-    sidebar_image="misc/rightside.png"
-    sidebar_image_bottom="misc/rightside-bottom.png"
-
 #ifdef TINY
     energy_image="misc/bar-energy-tinygui.png"
 #else
@@ -90,24 +82,17 @@
     defense_color_scale="ff0500,ff3700,ff6900,ff9b00,ffcd00,ffff00,cdff00,9bff00,69ff00,37ff00,05ff00"
 
     cross_image="misc/cross.png"
-    dot_image="misc/dot.png"
 
     footprint_prefix="footsteps/foot-normal,footsteps/foot-medium,footsteps/foot-slow"
     footprint_teleport_enter="footsteps/teleport-in.png"
     footprint_teleport_exit="footsteps/teleport-out.png"
 
-    missile_n_image=projectiles/missile-n.png
-    missile_ne_image=projectiles/missile-ne.png
-
     terrain_mask_image="terrain/alphamask.png"
     grid_image="terrain/grid.png"
     unreachable_image="terrain/darken.png"
-    void_image="terrain/void.png"
-    fog_image="terrain/fog.png"
 
     observer_image="misc/eye.png"
     tod_bright_image="misc/tod-bright.png"
-    download_campaign_image=""
 
     level_image="misc/icon-advance.png"