[release] 1.74.0 deadline for new libraries is almost here!

From: Marshall Clow (mclow.lists_at_[hidden])
Date: 2020-06-23 14:43:38

Tomorrow the master branch will be closed for new libraries and breaking changes.
See the calendar here for more dates:
        https://www.boost.org/development/ <https://www.boost.org/development/>

The next deadline is 1-July, when the master branch will be closed for major changes

Thanks,
— The Boost Release Team