Allow and truncate big tags in atomic's fetch_* (#7)
Allow and truncate big tags in atomic's fetch_* (#7)

* Allow and truncate big tags in atomic's fetch_*

* Revise documentation

* Allow big tags in initializer

* Remove validate_tag()

crossbeam-rs/crossbeam,aturon/crossbeam,crossbeam-rs/crossbeam,crossbeam-rs/crossbeam,crossbeam-rs/crossbeam