templatefilters: add "upper" and "lower" for case conversion Typically it will be used in patchbomb's flag template, which will be implemented by future patches.

repoview: improve compute staticblockers perf Previously we would compute the repoview's static blockers by finding all the children of hidden commits that were not hidden. This was O(number of commits since first hidden change) since 'children' requires walking every commit from tip until the first hidden change. The new algorithm walks all heads down until it sees a public commit. This makes the computation O(number of draft) commits, which is much faster in large repositories with a large number of commits and a low number of drafts. On a large repo with 1000+ obsolete markers and the earliest draft commit around tip~200000, this improves computehidden perf by 200x (2s to 0.01s).

hgweb: add phase to {changeset} template It's pretty surprising phase wasn't part of this template call already. We now expose {phase} to the {changeset} template and we expose this data to JSON. This brings JSON output in line with the output from `hg log -Tjson`. The lone exception is hweb doesn't print the numeric rev. As has been stated previously, I don't believe hgweb should be exposing these unstable identifiers. (We can add them later if we really want them.) There is still work to bring hgweb in parity with --verbose and --debug output from the CLI.

json: implement {changeset} template Output only contains basic changeset information for the moment. The format is compatible with `hg log -Tjson`.