* Fix formatting chrono durations to wide strings
* Make format buffers const correct
* Add FormatWide chrono test case
* Fix incorrect wide encoding of 'µs'
I think might be a source file encoding issue, so I used \u00B5 instead.
* Update FormatWide test to use proper encoding of µs
* Revert changes to format_localized's parameters
* Use different overload of `std::time_put<T>::put` to avoid needing a format string
* Use utf8_to_utf16 instead of having redundant overloads of get_units
* Revert some minor changes
* Remove FMT_CONSTEXPR from expression
This should hopefully fix compilation on VS <2019
* Make suggested changes from code review
* Run clang-format on chrono.h
* Make sure unit isn't null before constructing a string_view from it
1acb73f970