New features:

• math_log2 and math_exp2.
• GPI_Surface::RequestRender for windows.
• RequestRender for linux.
• Camera for android.
• RGB565 for data::Image.
• AtomicCompareExchange2.
• atomic_indexed_stack now support DCAS if available.
• YUV420sp for data::Image.

Fixed:

• Fixed UB in LinearLayout.
• Renamed GUI to UI.
• Modified GPI to use resource_ptr instead of raw pointers.
• ThreadQueue atomic ref counter.
• Refactored GUI to use separate data for arrange and post arrange.
• Fixed issue with DCAS under msvc.