Merge branch 'cc/bisect' (early part)

* 'cc/bisect' (early part): t6030: test skipping away from an already skipped commit bisect: when skipping, choose a commit away from a skipped commit bisect: add parameters to "filter_skipped" bisect: display first bad commit without forking a new process bisect: drop unparse_commit() and use clear_commit_marks()