parsers: add a C function to create a file foldmap This is a hot path on case-insensitive filesystems -- it's guaranteed to be called every time 'hg status' is run. This is significantly faster than the equivalent Python code: see the following patch for numbers.

util.h: define an enum for normcase specs These will be used in upcoming patches to efficiently create a dirstate foldmap.

perf: make measuring foldmap perf work again Rev 25c1d3ca5ff6 split the foldmap into two, but I forgot to update perf for the changes.

parsers._asciitransform: also accept a fallback function This function will be used in upcoming patches to provide a C implementation of the function to generate the foldmap.

util: add normcase spec and fallback These will be used in upcoming patches to efficiently create a dirstate foldmap.

hgk: display committer name when set by hg-git

jsonchangeset: set manifest node to "null" for workingctx Unlike changeset_printer, it does not hide the manifest field because JSON output will be parsed by machine where explicit "null" will be more useful than nothing.

jsonchangeset: set rev and node to "null" for workingctx

templater: tell hggettext to collect help of template functions

treemanifest: disable readdelta optimization When tree manifests are stored with one revlog per directory and loaded lazily, it's unclear how much readdelta will help. If only a few files change, then only a small part of the full manifest will be loaded, and the delta chains should also be shorter for tree manifests. Therefore, let's disable readdelta for tree manifests for now.