* Remove final specifier on Node::visit() to allow Scene to override it
Scene can now be visited correctly with valid cameras being set for child nodes when rendering outside of normal render loop.
* Add required copyright notice
* Allow HttpClient and Websocket implementations to be excluded from build
* Allow LLHTTP to be excluded from build
* Add descriptions of new options
* Rename options based on current convention of AX_ENABLE_XXX
* Update paths to lua bindings
* Update target include directories due to new extension dir structure
* Add missing libraries and paths for prebuilt option
* Current FairyGUI requires paths to parent and source directory
* Add required thirdparty search path to LUA library
* Restructure extension folder structure to reduce conflicts with project source files
* Do not include SDFGen headers for Android builds
* Ensure correct paths are included for the relevant targets
* ImGui is not be enabled for WinUWP, tvOS and iOS
* Fix LUA auto binding generator to work with updated extension folder structure
* Fix path and linker issues for yasio when using prebuilt option
Set correct paths to extensions for prebuilt option
* Fix memory leaks when axmol apps exit on non-embed systems
1. DriverBase no destroyInstance
2. Every object inherited from ax::Ref shoud destory before ScriptEngineManager, otherwise will trigger it's reinit and leak
3. QuadCommand always leak isolated indices
4. static singleton should'nt inhert from ax::Ref due to destory it before ScriptEngineManager impossible
5. Make Director don't inherit from ax::Ref due to it also cause ScriptEngineManager re-init, because we destroy ScriptEngineManger in destructor of Director
6. Explicit Director managed by Application and don't delete self at purgeDirector, since it will release at mainLoop and re-init in glView->pollEvents then leak
7. Rename ApplicationProtocol to ApplicationBase
8. Rename purgeDirector since we don't delete director self at it, maye rename to cleanup
9. Change ShaderCache to new/delete singleton, managed by ProgramManager
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Co-authored-by: lich426 <lich426@gmail.com>