Name ScreenContext, Refactor Course class to Track (#583)

* Rename Screen Contexts

* typedef ScreenContext struct

* Fix Compile

* Rename Course.cpp to Track.cpp

* Refactor Course to Track

* A few renames

* General Cleanup

* More Rename

* More names

* Move TrackSections struct to Track.h

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Co-authored-by: MegaMech <7255464+MegaMech@users.noreply.github.com>

docs/tutorials/boostramps.md

@@ -1,4 +1,4 @@
 \page boostramps Boost Ramps
 # Boost Ramps
 
-Boost ramps use a surface-type and is part of the course geography.
+Boost ramps use a surface-type and is part of the track geography.

docs/tutorials/paths.md

@@ -1,7 +1,7 @@
 @page paths Paths
-The game uses multiple types of course paths
+The game uses multiple types of track paths
 
-# Course Paths
+# Track Paths
 Used by courses