verify: report first bad changeset
- add linkrev and file arguments to err
- track lowest reported linkrev in err
- find linkrev in a couple cases
- sort linkrevs when reporting a bunch of errors against a file
- tidy up lots of messages
- make more robust against damaged indexes
- report first bad changeset if an error is encountered
running: init test1
result: None
running: add foo
result: None
running: commit -m commit1 -d 2000-01-01 foo
result: None
running: commit -m commit2 -d 2000-01-02 foo
result: None
running: log -r 0
changeset: 0:0e4634943879
user: test
date: Sat Jan 01 00:00:00 2000 +0000
summary: commit1
result: None
running: log -r tip
changeset: 1:45589e459b2e
tag: tip
user: test
date: Sun Jan 02 00:00:00 2000 +0000
summary: commit2
result: None