Light weight low level runtime library written in modern C++. (work in progress)

Support for Windows and Linux.

Define ART_THREAD_SAFE_CPU_INIT when compiling common/memory.cpp to synchronize CPU-feature detection across Memcpy, Memmove, Memset, and Memcmp. This uses the lightweight once primitive and needs no static TLS or OS synchronization calls. Without the definition, the existing CPU-feature initialization path is retained.