sshrepo: don't quote obviously safe strings (issue2983) This restores compatibility with hg-over-ssh servers that don't parse commandlines as sh does but works ok in the most common cases.

bookmarks: update and updatecurrentbookmark return status This makes bookmarks.update() and bookmarks.updatecurrentbookmark() return True or False to indicate whether the bookmark was updated or not. This allows callers to e.g. abort if the update failed.

bookmarks: clarify help for use of merge and update

merge: make 'nothing to merge' aborts consistent Makes the 'nothing to merge' abort messages in commands.py consistent with those in merge.py. Also makes commands.merge() and merge.update() use hints. The tests show the changes.