drqs-40608146: Additional format fixes in 2.17 for 'doxygen' conversion.

Import internal commit e42ace75d2fe3e5b4b623c64f124dfaa4a304a87
WIP new wording for timeutil

Import internal commit c87749b50abb18f16b59e0131e4c1e33e584ce96
Add #include <bslstl_algorithmworkaround.h> to non BSL_OVERRIDES_STD builds
atomics for gcc/arm working on armv7b (big endian) machine)
updated the arm atomics to make them work both on GCC and Clang
adjusted the architecture for arm build
const cast warnings in arm atomics
added implementation notes to arm atomics
Remove default.opts (DRQS 40974008)
bump version to 2.18.0
[APPROVAL] bump-version-to-2.18-drqs-41339858 to master
fixed bslstl::WideStringRef by making StringRef use char_traits
[APPROVAL] review/bsl-stringref-drqs41338618 to master
putting static/local functions in the bslstl_stringref test driver into an anonymous namespace to fix a build break
fixed namespace issue in bsls_platform; added arm atomics to gyp files
[APPROVAL] review/bsl-stringref-drqs41338618 to master
fixed namespace issue in bsls_platform
[APPROVAL] review/bsl-platform-namespace-drqs41495060 to master
Windows workaround for test drivers of unix headers

We have a couple of components that wrap standard POSIX
headeers that do not have a Windows equivalent.  It is
preferred for the component header to fail explicitly
on Windows when it tries to include the platform
header, rather than silently succeeding, only to fail
more subtly later when the user tries to make use of
the features declared in that header.  Hence, this
patch ammends the test drivers to perform a quick
platform detection before trying to include the
headers under test, avoiding the problem on Windows.
[APPROVAL] pending/master/fix-dual-stlmode-include-drqs41100790 to master