remove some unused old source
fix up button and checkbox gui-elements activating when GUI first
opened.  May need to revisit in the future for other elements.  Updates
#151
add screenshots/preview image for all structures in default pack
update client-proxy to enable a debug resolution setting upon game
launch
minor updates to instruction manual
update tooltip comment on survival-mode structure builder to use
lang-registry.  Closes #155
erm..fix typo in localization lookup for survival mode builder tooltip
key
minor updates to instruction manual
Merge branch '2.3' into 2.4