hgweb: move httpservice object from commands module This avoids the deep import of hgweb.server at the commands module.

merge: move almost all change/delete conflicts to resolve phase (BC) (API) We have finally laid all the groundwork to make this happen. The only change/delete conflicts that haven't been moved are .hgsubstate conflicts. Those are trickier to deal with and well outside the scope of this series. We add comprehensive testing not just for the initial selections but also for re-resolves and all possible dirstate transitions caused by merge tools. That testing managed to shake out several bugs in the way we were handling dirstate transitions. The other test changes are because we now treat change/delete conflicts as proper merges, and increment the 'merged' counter rather than the 'updated' counter. I believe this is the right approach here. For third-party extensions, if they're interacting with filemerge code they might have to deal with an absentfilectx rather than a regular filectx. Still to come: - add a 'leave unresolved' option to merges - change the default for non-interactive change/delete conflicts to be 'leave unresolved' - add debug output to go alongside debug outputs for binary and symlink file merges

test-merge-changedelete.t: print out debugmergestate We're going to use this to verify the merge state in upcoming patches.

debugmergestate: also recognize change/delete conflicts in the merge state We're going to use this for tests in upcoming patches.

debugmergestate: print out null nodes as 'null' This is so much easier to read than a long string of zeroes, and we're going to have a lot more of these nodes once change/delete conflicts are part of the merge state.

test-merge-force.t: check .orig files separately We're going to soon compare the output of all the non-orig files before and after a resolve, and this makes that more convenient. The .orig files are obviously going to differ between the two.

merge.recordupdates: mark 'a' files as added unconditionally See the previous patch for why we do this.

merge: add a new action type representing files to add/mark as modified This is somewhat different from the currently existing 'a' action, for the following case: - dirty working copy, with file 'fa' added and 'fm' modified - hg merge --force with a rev that neither has 'fa' nor 'fm' - for the change/delete conflicts we pick 'changed' for both 'fa' and 'fm'. In this case 'branchmerge' is true, but we need to distinguish between 'fa', which should ultimately be marked added, and 'fm', which should be marked modified. Our current strategy is to just not touch the dirstate at all. That works for now, but won't work once we move change/delete conflicts to the resolve phase. In that case we may perform repeated re-resolves, some of which might mark the file removed or remove the file from the dirstate. We'll need to re-add the file to the dirstate, and we need to be able to figure out whether we mark the file added or modified. That is what the new 'am' action lets us do.

mergestate: add a cached property accessor for the local context This is going to be useful in an upcoming patch. We make this a public accessor because this is also going to be useful for custom merge drivers.

mergestate: raise exception if otherctx is accessed but _other isn't set We don't want to inadvertently return the workingctx (self._repo[None]).