HIII:PE update #4 - Steam Achievements

Now you can prove your worth by unlocking the following Achievements:

* SOULREAPER: 100M score!
* SOULGRINDER: 1 MILLION SOULS!
* 5K Souls in 1 game.
* 10K Souls in 1 game.
* 20K Souls in 1 game.
* COMBO MASTER: 5K Combo!
* LEVEL 00 CLEAR!
* LEVEL 01 CLEAR!
* LEVEL 02 CLEAR!
* LEVEL 03 CLEAR!
* LEVEL 04 CLEAR!
* LEVEL 05 CLEAR!
* LEVEL 06 CLEAR!
* LEVEL 07 CLEAR!
* LEVEL 08 CLEAR!
* LEVEL 09 CLEAR!
* RETRO MODE CLEARED!

Also added: an interface element in the level select screen signifying level completion.