templatekw: allow getlatesttags() to match a specific tag pattern
This will allow the latest class of tag to be found, such as a release candidate
or final build, instead of just the absolute latest. It will be exposed in a
future patch.
It's unfortunate that the original 'latesttags' cache can't be used to determine
the proper values, but it isn't fully populated for the entire repo. For
example, the {latesttagdistance} keyword on the Mecurial repo builds the cache
up back to the revision for 1.4. If the pattern was 're:^0\.\d$', that wouldn't
be in the cache. Maybe this can be optimized some other way, but for now, this
is the simpliest implementation.
Ancestors of 5
4 2 0
Ancestors of 6 and 5
3 4 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 3 4 2 1 0
Ancestors of 7, 5 and 3, including revs
7 5 3 6 4 2 1 0
Descendants of 5
7 8
Descendants of 5 and 3
6 7 8
Descendants of 5 and 4
5 7 8