Changed to new declaration syntax.  Now declaration must specify variable that holds matrix operator name.  This allows matrix command to place a trace on any unset of the variable, in which case it can clean up after itself.  I.e. when a matrix is declared locally, it goes away automatically when the proc exits (note to itcl users: since itcl does not let you place traces on class data, you will need to either make it global or create a destructor for it).
Changed to new declaration syntax.  Now declaration must specify variable
that holds matrix operator name.  This allows matrix command to place a
trace on any unset of the variable, in which case it can clean up after
itself.  I.e. when a matrix is declared locally, it goes away
automatically when the proc exits (note to itcl users: since itcl does not
let you place traces on class data, you will need to either make it global
or create a destructor for it).

svn path=/trunk/; revision=985

FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot