Oops, feeding garbage to the SolveSpace file load routines would

make it return with the program in a bad state and blow up later;
so fix at least one easy case of that.

[git-p4: depot-paths = "//depot/solvespace/": change = 2114]

file.cpp

@@ -464,6 +464,10 @@ bool SolveSpace::LoadFromFile(char *filename) {
     if(fileLoadError) {
         Error("Unrecognized data in file. This file may be corrupt, or "
               "from a new version of the program.");
+        // At least leave the program in a non-crashing state.
+        if(SK.group.n == 0) {
+            NewFile();
+        }
     }
 
     return true;

wishlist.txt

@@ -1,15 +1,15 @@
 replace show/hide links with icons?
 lock point where dragged constraint
 projected and signed distance constraints
+rounding, as a special group
+associative entities from solid model, as a special group
 
 -----
 better level of detail
-associative entities from solid model, as a special group
 some kind of import
 faster triangulation
 loop detection
 IGES export
 incremental regen of entities
-rounding, as a special group