Cosmetic cleanups

Removed a warning
Added a try-catch
Added some fprintf for clarity

code/classes/SCDclass_mdspar.m

@@ -74,6 +74,8 @@ classdef SCDclass_mdspar < matlab.mixin.Heterogeneous
     % Not abstract methods common to all child classes
     methods
         function mdsconnect(obj, shot)
+            assert(~~exist('mdsconnect','file'),...
+                'SCD:NoMDS','mdsconnect not found, are the mds matlab tools installed?')
            mdsconnect(obj.mdsserver);
            s=mdsopen(obj.mdstree, shot);
            str=sprintf('SCDclass_mdsparam (%s), failed opening MDS+ tree', obj.modelparam);