Use clang-tidy to check more code conventions (#4214)

* Create clang-tidy.sh
* Add clang-tidy to circle.yml
* Fixed some naming violations

Fixes #4164

src/NetherPortalScanner.h

@@ -39,8 +39,8 @@ private:
 	static const int SearchSolidBaseWidth = 3;
 
 	/** Where to place the player out from the face and across the face */
-	const double OutOffset = 2;
-	const double AcrossOffset = 0.5;
+	static const double OutOffset;
+	static const double AcrossOffset;
 
 	/** Builds a portal. */
 	void BuildNetherPortal(Vector3i a_Location, Direction a_Direction, bool a_IncludePlatform);