Change the order in which entities are allocated.
Change the order in which entities are allocated.

This change allows the editor to preserve the entity order
when it outputs the entity list, rather than reversing it each
time.

This will allow json file merging to happen much more nicely via
git, for entity lists.

Change-Id: Ia4a362053a5e8aba8fd04db0ed3f29d2f8f6449e
Tested: Ran game on Linux with no major issues.

google/corgi,google/corgi