error::enable_stacktrace() refactoring.
BUNSAN_EXCEPTIONS_WRAP_WRAPPER() bug fix.
enable_error_info() refactoring.
runtime::stacktrace::get(): skip parameter semantics change.
error: nested exception support.

enable_error_info refactoring.
categorized_error refactoring.

error_code_message was removed.
boost::to_string(categorized_error::error_code) implementation.
enable_error_info() documentation fixes.
BUNSAN_EXCEPTIONS_WRAP_LIST style fix.