relnotes: copy contents of "next" to "5.8" and clear "next" The same procedure as every year^Wcycle. Unlike previous cycles, I haven't actually recorded the copy because we don't want to propagate further changes in "next" (from the stable branch) to "5.8". Differential Revision: https://phab.mercurial-scm.org/D10500

== New Features ==
 

== Default Format Change ==

These changes affects newly created repositories (or new clone) done with
Mercurial 5.8.


== New Experimental Features ==


== Bug Fixes ==


== Backwards Compatibility Changes ==


== Internal API Changes ==