make projectiles cover a simple table

combat.tex

@@ -402,14 +402,11 @@ ignoring all \gls{dr}.
 All projectiles suffer from the need to reload.
 As with picking up any other item, characters must spend least 1~\gls{ap} to take out and use arrows.
 
-\paragraph{Cover}
-provides a variable Bonus, depending on the size.
-
-\begin{boxtable}
+\begin{nametable}{Projectiles Cover}
   +1 & Large bushes \\
   +2 & Tower shield \\
   +3 & Murder hole  \\
-\end{boxtable}
+\end{nametable}
 
 \subsubsection{The Long Bow}
 \index{Projectiles!Bow}