ignore the pointer to the menu window when it's NULL
fix item description
Move '$' symbol to beggining of the price
Merge branch 'item_description' of https://github.com/illi-kun/Cataclysm-DDA into illi-kun-item_description
Merge branch 'fix-ui-menu-window-crash' of https://github.com/BevapDin/Cataclysm-DDA into BevapDin-fix-ui-menu-window-crash