Move cmdtable and reposetup handling out of extensions.py
A new function (extensions.extensions) allows the code that is
interested in those attributes to handle them directly.
This allows some cleanups of extensions.py. Notably, we can
remove the extensions.commandtable hack.
It also makes it easier to add standard extension attributes,
like a "hgwebsetup" function or a "helptable" dict that augments
the data in help.py, etc.
adding a
adding b
adding dir.h/foo
adding t.h
adding t/b
adding t/e.h
adding t/x
hg locate a
a
locate succeeded
hg locate NONEXISTENT
locate failed
hg locate
a
b
dir.h/foo
t.h
t/b
t/e.h
t/x
hg locate a
hg locate NONEXISTENT
hg locate relpath:NONEXISTENT
hg locate
b
dir.h/foo
t.h
t/b
t/e.h
t/x
hg locate -r 0 a
a
hg locate -r 0 NONEXISTENT
hg locate -r 0 relpath:NONEXISTENT
hg locate -r 0
a
b
dir.h/foo
t.h
t/b
t/e.h
t/x
% -I/-X with relative path should work
hg locate
b
dir.h/foo
t.h
t/b
t/e.h
t/x
hg locate -I ../t
t/b
t/e.h
t/x
hg locate t/**
t/b
t/e.h
t/x
hg locate b
../b
../t/b
hg locate *.h
../t.h
../t/e.h
hg locate path:t/x
../t/x
hg locate re:.*\.h$
../t.h
../t/e.h
hg locate -r 0 b
../b
../t/b
hg locate -r 0 *.h
../t.h
../t/e.h
hg locate -r 0 path:t/x
../t/x
hg locate -r 0 re:.*\.h$
../t.h
../t/e.h