Shared Libraries:  In the FLAT build mode, kernel modules may be used to provide minimal shared library functionality.

Fix a compile error: in sched_cpuload.c:Line136, the variables ts and secs are not defined if CONFIG_CPULOAD_ONESHOT_ENTROPY = 0. However, these variables are used regardless of CONFIG_CPULOAD_ONESHOT_ENTROPY at lines~180:onwards.

ARM memcpy():  Use DWord vs. HWord offset.  ARM 32-bit instructions must be aligned to DWord boundaries and this gives us more range in the jump tables.

Adding missing CONFIG_ prefix

Move optimized ARM memcpy functions from arch/arm/src/ to libc/machine/.  This is necessary for the PROTECTED and KERNEL build modes.  Otherwise, memcpy() will be built in to kernel space and not accessible to applications.

Eliminate CONFIG_ARCH_OPTIMIZED_FUNCTIONS.  Move options to select architectur-specific C library options from libc/Kconfig to libc/machine/Kconfig and rename.

SAM3/4: Add support for ATSAM4S4C.

STM32L4:  Port fix for multiple oneshot timers from STM32.  Also fixes a few issues with original STM32 implementation.

Fixed some issues that prevented ipv6 to work with ipv4 enabled.