Topic/default/issue631 support for topics
Adds features to enable working with topics:
- Viewing the current topic in project decorations
- Viewing the list of topics in a repo and identifying the active topic (
hg topics --age
) - Viewing the changesets of the active topic (
hg topics --list
) - Creating a topic
- Switching to an existing topic so that future commits are assigned to that topic
- Clearing the active topic if any
- Enabling a preference setting for systematically pushing ancestry trees (so that only the current topic will be pushed to a remote server).