ENH: max clone num increased to 1000

For some application like Lego bricks, 100 is far from enough.

Jira: none
Change-Id: I94a6f47e75545bf35f16e493eb4bb05236ea98fe
(cherry picked from commit 2a4270adaaf7d14eb8b3d0397264df28b20a1ea2)

src/slic3r/GUI/Plater.cpp

@@ -12012,7 +12012,7 @@ void Plater::clone_selection()
     long res = wxGetNumberFromUser("",
         _L("Clone"),
         _L("Number of copies:"),
-        1, 0, 100, this);
+        1, 0, 1000, this);
     wxString msg;
     if (res == -1) {
         msg = _L("Invalid number");