makefile: reformat .PHONY targets The list of make targets is likely to evolve over time. This reformats streamlines future patches.

makefile: mkdir is not needed on templatized docker builds This imitates e63dfbbdbd07 and is a small addition to 231690dba9b4 and 5c1283713293

hgweb: convert _siblings to a factory function of mappinggenerator IIUC, only reason it was a class is to make the generator restartable, which is now served by the mappinggenerator.

hgweb: extract a generator function of _siblings class _siblings will be converted to a plain function.

hgweb: wrap {changenav} and {nav} with mappinglist

hgweb: make revnav.gen() simply build a list of mappings by one pass There was actually no lazy stuff.

hgweb: lift {sessionvars} to a wrapped type Since a sessionvars object is updated in-place, we can't simply wrap it by mappinglist.

hgweb: make sessionvars class less dense

hgweb: prefix private variables of sessionvars with '_'

lfs: update the HTTP status codes in error cases I'm not bothering with validating PUT requests (for now), because the spec doesn't explicitly call out a Content-Type (though the example transcript does use the sensible 'application/octet-stream').