localrepo: remove 'closed' argument to heads(...) function
- repository heads are not associated with the closed attribute, so
remove it making the code in line with the concept.
- Fix functions that were calling heads with the parameter.
- Adjust webcommands.branches to include the concept of inactive
as well as open and closed branches
- Fix code and docstrings in commands to make the correct use of
closed branches & branch heads clearer
- Improve grammar of 'hg heads' help text (2nd submission)
this does not alter the cli for hg branches, that work is
still to be done
Ancestors of 5
4 2 0
Ancestors of 6 and 5
3 4 2 1 0
Ancestors of 5 and 4
4 2 0
Descendants of 5
7 8
Descendants of 5 and 3
6 7 8
Descendants of 5 and 4
5 7 8