Fix hg push and hg push -r sometimes creating new heads without --force.
Fixing issue179.
The algorithm checks if there not more new heads on the remote side than heads
which become non-heads due to getting children.
Pushing this repo:
m
/\
3 3a|
|/ /
2 2a
|/
1
to a repo only having 1, 2 and 3 didn't abort requiring --force before.
Added test cases for this and some doc strings for used methods.
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
verify failed
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
commit failed