RCORE: strerror ambiguity fixup
UI: renamed exit_app() to avoid conflicts with libc
RCORE: provide aligned_alloc/aligned_free, fmsb, IdAllocator in memory.*[hc]
RCORE: provide AlignedArray<> + test, originally implemented by Stefan Westerfeld
RCORE: ignore multiple init_core() calls
RCORE: export cstring_to_bool
RCORE: add general purpose debug_envkey_* API, migrate RAPICORN_DEBUG
RCORE: rename rapicorn_debug_enabled
UI: use rapicorn_debug_enabled
RCORE: provide envkey_flipper_check, envkey_debug_check, envkey_debug_message
RCORE: document $RAPICORN_FLIPPER and rapicorn_flipper_check()
RCORE: use rapicorn_flipper_check() for QuickTimer configuration
RCORE: allow caching of envkey_flipper_check()
RCORE: remove obsolete exception code
RCORE: properly document RAPICORN_FLIPPER and __FILE_DIR__
RCORE: redefine assert() after including assert.h, improve docs
RCORE: remove RAPICORN_DEBUG convenience variant, it produced too many conflicts
RCORE: provide RAPICORN_BREAKPOINT, don't provide convenience variant
RCORE: docu fixes for $RAPICORN_DEBUG
RCORE: improve macro documentation