* Fix compilation with -Wsign-conversion
For tests with GCC and Clang
Fixes https://github.com/ETLCPP/etl/issues/632
* Fix support of negative Id in type_lookup.h: type_from_id
* Fix element access arithmetic in atomic_gcc_sync.h fetch_add/fetch_sub
* Fix rounded_integral_division.h: divide_round_half_odd(): direction is always 1
* Fix optimized tests by suppressing warning from STL
* Fix uninitialized buffer in hash for month_weekday
* Fix overlapping memcpy with memmove
* Fix random out of bounds index in __builtin_memmove
Suppressing compiler warning
* Fix array bounds warnings from static casts in message_router
In compiled code, casting to wrong message types is generated,
even though the code paths are supposed to be never taken due to runtime
msg id checks. Therefore, the warnings can be suppressed.
* Fix syntax errors in base64 decoder tests
* Fix test failure in test_rounded_integral_division.cpp when optimized
When building tests optimized, test_round_to_half_even_signed_limits
fails due to the fact that
etl::absolute(std::numeric_limits<int32_t>::min()) < 0
