Updated README.md, fix typo(s) (#3376)

Author: Bob Conan

README.md

@@ -208,7 +208,7 @@ width="640" height="480" border="0" /></a>
 ## Ethereal Engine
 
 https://github.com/volcoma/EtherealEngine - EtherealEngine is a C++ game engine
-and WYSIWYG dditor.
+and WYSIWYG editor.
 
 ![EtherealEngine screenshot](https://user-images.githubusercontent.com/1499411/29488403-ff3c3df6-8512-11e7-869f-32a783530cc3.png)
 
@@ -246,7 +246,7 @@ width="640" height="480" border="0" /></a>
 
 http://www.smithandwinston.com/ - Smith and Winston is an exploration twin stick
 shooter for PC, PS4 & XBoxOne arriving in late 2018. Smith and Winston features
-a massively destructable voxel world, rapid twin stick combat, physics puzzles
+a massively destructible voxel world, rapid twin stick combat, physics puzzles
 and Metroid-style discovery.
 
 <a href="http://www.youtube.com/watch?feature=player_embedded&v=Mr_L7KuiByU"