Merge pull request #376 from jonaslandsgesell/master

added explicitly that espresso uses a cuboid box

doc/ug/setup.tex

@@ -62,7 +62,7 @@ \section{\texttt{setmd}: Setting global variables.}
 \todo{Which commands can be used to set the \emph{read-only}
   variables?}
 \begin{globvar}
-\item[box_l] (double[3]) Simulation box length. Note that
+\item[box_l] (double[3]) Simulation box lengths of the cuboid box used by Espresso. Note that
   if you change the box length during the simulation, the folded
   particle coordinates will remain the same, i.e., the particle stay
   in the same image box, but at the same relative position in their