String freeze on July 22nd

[Mark Doliner]

Hi devs!  We've got a little security thing to patch, so we're going
to try to push 2.7.2 out the door over the next few weeks.  Here's the
proposed timeline:
July 22 - String freeze
July 29 - Tag, build, and provide tarballs to distributions so they
can prepare to packages before the embargo date
August 5 - Release to the public and announce the security thing

Lemme know if there are any questions!
--Mark