convert: option to set date and time for svn commits Converting to subversion repository is not preserving original commit dates as it may break some subversion functionality if commit dates are not monotonically increasing. This patch adds `convert.svn.dangerous-set-commit-dates` configuration option to change this behaviour and enable commit dates convertion for those who want to take risks. Subversion always uses commit dates with UTC timezone, so only timestamps are used. Test `test-convert-svn-sink.t` uses `svnxml.py` script to dump history of svn repositories. Atm the script is not printing `date` field from svn log. This patch changes this to allow checks on correctness of date and time convertion. Documentation is updated. Additional test case is added to test commit dates convertion. Differential Revision: https://phab.mercurial-scm.org/D9721

copies: simplify the conditional for _filter's case 3 The conditional is much simpler and the test are actually happier. This clarification of the conditional will also be necessary to properly support tracing more renames in a coming changeset. Differential Revision: https://phab.mercurial-scm.org/D9795

copies: clarify which case some conditional are handling This make the function a bit clearer. The middle conditional get no label because we about about to remove it. See next changeset for details. Differential Revision: https://phab.mercurial-scm.org/D9794

copies: explicitly filter out existing file in graftcopies The `graftcopies` function does something very strange (maybe even wrong), it calls `_filter` with a pair of changeset that does not match the one used to compute the copies informations. We are about to do some rework of `_filter` to make it closer to its documented intent and fix a couple of bug. This means some of the logic that only make sense for graft need to go somewhere else. We add the extra filtering with proper documentation to `graftcopies`. Differential Revision: https://phab.mercurial-scm.org/D9802