largefiles: extract test-lfconvert.t from test-largefiles.t
test-largefiles.t is getting pretty big, and there's lots more to test
in lfconvert. And lfconvert is a fairly orthogonal feature to the
rest of largefiles.
Test the GPG extension
$ "$TESTDIR/hghave" gpg || exit 80
$ cat <<EOF >> $HGRCPATH
> [extensions]
> gpg=
>
> [gpg]
> cmd=gpg --no-permission-warning --no-secmem-warning --homedir $TESTDIR/gpg
> EOF
$ hg init r
$ cd r
$ echo foo > foo
$ hg ci -Amfoo
adding foo
$ hg sigs
$ hg sign 0
Signing 0:e63c23eaa88a
$ hg sigs
hgtest 0:e63c23eaa88ae77967edcf4ea194d31167c478b0
$ hg sigcheck 0
e63c23eaa88a is signed by:
hgtest