* Put all of TitleSequenceManager into the same namespace
* Move RideConstructionState into the OpenRCT2 namespace
* Adopt existing namespaces into OpenRCT2 namespace
This adds `using namespace OpenRCT2` to compilation units where appropriate,
as a means to get the codebase to compile until these units have been placed
in a namespace of their own.
* Split off path addition paint calls
* Replace occurences of “path bit” with “path addition”
* Replace occurences of “footpath item“ with “path addition”