templatekw: add compatdict() as a replacement for showdict() This is mostly a copy of showdict(), which will be deprecated later. See the docstring for why it's called a "compat" dict. showenvvars() is ported to the new API as an example.

templatekw: pass templater to _showlist() by an explicit argument Prepares for switching to the (context, mapping) API.

hgweb: make templater mostly compatible with log templates Prepares for gradually switching templatekw.showsuccsandmarkers() to new API. This was a PoC showing how to reuse templatekw functions in hgweb. We could remove rev, node, author, etc. from the commonentry() table, but we'll have to carefully remove all corresponding symbols from webcommands.*(). Otherwise, we would face the issue5612. Still templatekw.keywords aren't exported. Otherwise some tests would fail because the atom template expects {files} to be empty in filelog, but templatekw.showfiles() provides the {files} implementation.

log: do not invoke templatekw.showobsfate() as a function Prepares for switching to the (context, mapping) API. I tried, but it appeared not an one-off change to extract a non-template function from showobsfate(), which deeply depends on the templater internals.

templatekw: inline getfiles() It's just three lines. We don't need a separate function for that.

templatekw: factor out function to build a list of files per status Removes copy-paste code before switching to the (context, mapping) API.