Enabled safe extension API flag on project level
Enabled safe extension API flag on project level

This refines #50 and applies the change to the macOS target as well.

Signed-off-by: Lukas Kubanek <a9cb54f1647e7411728256e0083eda6c28a16504@me.com>

lukaskubanek/OrderedDictionary,lukaskubanek/OrderedDictionary