When the topic branch is deleted only the label is removed, commits
are stayed in the database, they are now merged into v2::
- --o--o--o--o--o--o-M-<v2 - it is the mainline branch
- \ /
- --*--*--* - it is the topic branch, now unnamed
+ o--o--o--o--o--M--< v2 - it is the mainline branch
+ \ /
+ --*--*--* - it is the topic branch, now unnamed
The topic branch is deleted to avoid cluttering branch namespace with
small topic branches. Information on what issue was fixed or what