commands: use keyword arguments in update function
This will help us in having a dictionary with the values of all the arguments
and we can add more flags without adding an argument to the function.
Differential Revision: https://phab.mercurial-scm.org/D2896
https://bz.mercurial-scm.org/1089
$ hg init
$ mkdir a
$ echo a > a/b
$ hg ci -Am m
adding a/b
$ hg rm a
removing a/b
$ hg ci -m m a
$ mkdir a b
$ echo a > a/b
$ hg ci -Am m
adding a/b
$ hg rm a
removing a/b
$ cd b
Relative delete:
$ hg ci -m m ../a
$ cd ..