merge: add hints about the use of 'hg heads' to find the rev to merge

prepush: warn about every new outgoing named branch, not just the first

prepush: rename variables, refactor

rebase: add --detach option to detach intermediate revisions (issue1950) When rebasing an intermediate revision, rebase keeps a parent relationship with the original parent. This option forces the removal of this relationship. In more depth, it 'fakes' null merges between the target revision and the ancestors of source, dropping every change from the ancestors. The result is that every change in source and its descendants will be rebased, ignoring the changes in its ancestors.

rebase: refactoring Separate rebase-specific functions, in order to provide a better base to extend rebase's capabilities. Note that this will be useful especially to share functions with 'adapt'.

commands: do all branch heads by default, demote topological to -t/--topo

commands: actually implement --closed for topological heads

commands: externalize branchheads so we can do it for all branches at once

commands: move inactive/closed out so they can have more effect

commands: don't do too much work for error messages

commands: allow --closed even for topological heads displays But it actually only starts working later on.

util: make spawndetached() handle subprocess early terminations The file-based synchronization introduced by e22695b4472f hangs when the child process fails before terminating the handshake, which the previous pipe-based version handled correctly. To fix this, the parent polling loop was fixed to detect premature terminations of the child process.

zeroconf: do not try to encode encoded strings (issue1942)

zeroconf: override default destination folder on clone