0.872 Version Released!

Firstly, please accept my apologies. I misplaced a number in easy mode so level 1-1 became even harder than hard mode. But I've fixed it. And here's a detailed list changed in 0.872 version. - Brand new training level. Please have a try and tell me what do you think. - Now Escape key opens menu during gameplay. - A fast game over mode has been added. Now you can skip the game over screen and restart from the last checkpoint immediately. - Soundtracks update. - Added an option to the pause screen to allow player restart game from the last checkpoint. - Fixed a bug where sometimes the game freezes at the game clear screen. - Fixed a bug that turrets receiving damage from an unknown source. - Fixed a configuration of level 1-1 in easy mode. (oops) Demo version got fixed too. Cheer!