Add 'mgs' to Ghostscript binary search list

Included 'mgs' in the list of Ghostscript binaries checked on Windows systems to improve compatibility with alternative Ghostscript installations.

Author: markmikkelsen

export_fig/ghostscript.m

@@ -86,7 +86,7 @@
     end
     % Check whether the binary is on the path
     if ispc
-        bin = {'gswin32c.exe', 'gswin64c.exe', 'gs'};
+        bin = {'gswin32c.exe', 'gswin64c.exe', 'gs', 'mgs'};
     else
         bin = {'gs'};
     end