version: change "place" field of extension to "bundled" flag
The name "place" sounds odd. We can simply expose raw boolean values instead
of switching external/internal literals.
extensions: use ismoduleinternal() thoroughly
"ships-with-hg-core" would be long enough to typo.
lock: show more detail for new-style locks in lock waiting message (
issue4752)
Improve the lock waiting warning message by explicitly saying that a host and
process are holding the lock. This nudges confused new users in the direction
of investigating the other process instead of removing the lock.