Update CODINGSTYLE.md

Spotted some minor typos, improved some wordings

CODINGSTYLE.md

@@ -60,7 +60,7 @@ Markers to indicate a compound statement should be on the same line.
 ### Spacing
 All keywords and operators are separated by a space.
 
-For cleanliness sake, make sure there are no trailing whitespaces.
+For cleanliness sake, ensure there is no trailing whitespace.
 
 ## Identation
 Indentation is one tab character per level, alignment is done using spaces.