apiVersion vs branch (v1.2 vs v1.3)

[dacap]

The app.apiVersion is not a good way to check for API features when we have this branch of versions (e.g. v1.2 and v1.3). We think that we could add a new object to check features:

if app.features.hasTilemapLayers then
  ...
end

In case of a property that doesn't exist is used (e.g. app.features.nonExistentFeature) it just return false (instead of a Lua error).