gitweb: provide links to branches, tags and bookmarks by name
This is adapted from
cd842821db2c, that was added to paper for 3.5 release.
It adds another way to refer to branches, tags and bookmarks in urls: by name.
It's still possible to navigate to a specific changeset hash, but now you can
get more descriptive urls straight from /summary page, for example.
branchentry template (and so the whole branches table on /summary and
/branches) lost the column that had a plain changeset hash, because tags and
bookmarks don't have this column and also because there is already a way to
address branch by its changeset hash (changeset link just next to it). Maybe we
can instead bring this column with a plain changeset hash to tags and
bookmarks, but this, more terse, new look feels fine.
$ hg init
$ echo This is file a1 > a
$ hg add a
$ hg commit -m "commit #0"
$ ls
a
$ echo This is file b1 > b
$ hg add b
$ hg commit -m "commit #1"
$ hg co 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
B should disappear
$ ls
a