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

adding base
abort: qdelete requires at least one revision or patch name
abort: cannot delete applied patch c
Now at: b
a
b
a
b
series
status
Now at: a
a
b
series
status
1 [mq]: a
0 base
abort: cannot delete revision 3 above applied patches
f
4 [mq]: f
3 [mq]: e
2 [mq]: d
1 [mq]: a
0 base