manifest: Add patch to fix clear_all button

Author: sparshg

org.sugarlabs.Physics.json

@@ -111,6 +111,10 @@
                     "type": "patch",
                     "path": "physics-port.patch"
                 },
+                {
+                    "type": "patch",
+                    "path": "physics-fix-destroy.patch"
+                },
                 {
                     "type": "patch",
                     "path": "physics-monitors.patch"

physics-fix-destroy.patch

@@ -0,0 +1,14 @@
+diff --git a/tools.py b/tools.py
+index 78108fe..3f3c4b3 100644
+--- a/tools.py
++++ b/tools.py
+@@ -98,7 +98,8 @@ class Tool(object):
+                 elif event.action == 'clear_all':
+                     # Get bodies and destroy them too
+                     for body in self.game.world.world.bodies:
+-                        self.game.world.world.DestroyBody(body)
++                        if body != self.game.world.world.groundBody:
++                            self.game.world.world.DestroyBody(body)
+ 
+                     # Add ground, because we destroyed it before
+                     self.game.world.add.ground()