Update 0.2.0

New Features:

• https://trello.com/c/HHKaPEKh/1-add-permanent-upgrade-functionality
• https://trello.com/c/H2qh36W9/9-credits-screen
• https://trello.com/c/8g7DYccg/18-add-timer-for-survival-time
• https://trello.com/c/DoWwGpYZ/15-add-ui-element-for-tracking-experience

Fixes:

• https://trello.com/c/pCFDGp5A/27-bug-player-taking-damage-and-dies-from-unknown-source

Screenshots: