Typos / Readme.md

[VladimirCreator]

There are a few typos:

1. line №5

“…In this case, the player (game objets)…” should be replaced with
“…In this case, the player (game objects)…”.

2. line №15

“…entities that have a Healt…” should be replaced with
“…entities that have a Health…”

3. line №17

“…this sytem is needed…” should be replaced with
“…this system is needed…”.