Log Message:
Update to 2.6.2:

This is a regularly-scheduled bugfix release.

    amend: complain more comprehensibly about subrepos
    blackbox: fix blackbox causing exceptions in tests
    blackbox: fix recording exit codes (issue3938)
    dirstate: don't overnormalize for ui.slash
    graft: refuse to commit an interrupted graft (issue3667)
    help: fix role/option confusion in RST
    help: stop documentation markup appearing in generated help