Bug fixes and a little polish v1.2.0

Changelogs:

• Fixed the floaty feels in player movement, improve jump input to be more responsive.
• Health potions now no longer apply unwanted knock-backs.
• Spikes now try to push player to either sides if player landing on top of them.
• Camera now follows ahead of player if he descends faster than its move speed.
• Player now can properly fit through 1-tile horizontal gaps.