filemerge: put temporary files in single temp dir by default
The feature introduced in D2888 seems like a pure improvement to
me. It makes the names' of temporary file easier to read. Let's have
it always enabled.
I also removed the config option for the path prefix because it
doesn't seem useful. I asked Kyle (the author of the feature) about it
and he couldn't think of a reason to keep it. I suspect it was just
that we to have a config to turn it on/off while it was experimental,
so it might as well be a configurable prefix then.
Differential Revision: https://phab.mercurial-scm.org/D12171
Ancestors of 5
4 2 0
Ancestors of 6 and 5
4 3 2 1 0
Ancestors of 5 and 4
4 2 0
Ancestors of 7, stop at 6
6
Ancestors of 7, including revs
7 6 5 4 3 2 1 0
Ancestors of 7, 5 and 3, including revs
7 6 5 4 3 2 1 0
Descendants of 5
7 8
Descendants of 5 and 3
6 7 8
Descendants of 5 and 4
5 7 8