requirements: introduce a set of working directory specific requirements
Some requirements like the SPARSE_REQUIREMENT is working directory specific and
cannot be shared. We add a set which will contain all these requirements.
This is not the best we can do, I think having a rich requirement class will be
much better but that will be out of scope for this series.
Differential Revision: https://phab.mercurial-scm.org/D8924
$ cat >> $HGRCPATH << EOF
> [extensions]
> fastannotate=
> EOF
$ hg init repo
$ cd repo
changes to whitespaces
$ cat >> a << EOF
> 1
>
>
> 2
> EOF
$ hg commit -qAm '1'
$ cat > a << EOF
> 1
>
> 2
>
>
> 3
> EOF
$ hg commit -m 2
$ hg fastannotate -wB a
0: 1
0:
1: 2
0:
1:
1: 3