writebundle: add a compression argument for the bundle2 case
Bundle2 compression is more complex than the bundle1 one. Therefore it
is handled by the bundler itself. Moreover, on-disk bundle2 will
probably have a large number of flavors so simply adding a new "format"
for it does not seems the way to go.
This will be used in the next changeset to compress bundle2 strip backup.
strip: use bundle2 + cg2 by default when repository use general delta
The bundle10 format (plain changegroup-01) does not support general delta and
result into expensive delta re-computation when stripping. If the repository is
general delta, we store backups as bundle20 containing a changegroup-02 payload.
We remove the experimental feature related to strip backup bundle format because
this achieve the same goal in a leaner way. Removing the experimental option is
fine, that is why it experimental in the first place.
Compression of these bundles are coming in later changesets.
Added signature for changeset
9a466b9f9792