stack: use repo.revs() instead of revsetlang.formatspec() + scmutil.revrange()
Using scmutil.revrange() it's possible to use multiple revsets at the same
time, but we're not using that functionality in stack.
I thought maybe that function could be used to make stack definition
customizable (by combining various parts into one set), but scmutil.revrange()
gives the union of all provided revsets, which is not very useful in stack's
case (we want "and" between parts, not "or").
Mercurial
=========
Mercurial is a fast, easy to use, distributed revision control tool
for software developers.
Basic install::
$ make # see install targets
$ make install # do a system-wide install
$ hg debuginstall # sanity-check setup
$ hg # see help
Running without installing::
$ make local # build for inplace usage
$ ./hg --version # should show the latest version
See https://mercurial-scm.org/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.