feature: update for Godot 3.3-stable

[resinten]

Update to support changes in Godot 3.3. Mostly, this involves updating Thread (modernized to use start instead of create) and atomic_increment (now SafeNumeric<T>). Also removed c++11 flag from SCsub, as Godot now uses features from newer editions of C++ (std::shared_timed_mutex).

While in the code, I fixed a few typos that I found:
partern/parttern => pattern
applay => apply
DECLAR_ => DECLARE_
DECLEARATION => DECLARATION

[Geequlim]

Thanks!