filemerge: use revset notation for p1/p2 of local/other descriptions

tests: fix for failure of test-convert-p4-filetypes.t Before this patch, test-convert-p4-filetypes.t fails (at least with 2015.2/1366233 version of p4/p4d), because some files below are omitted in expected output for revision 1. - file_tempobj - file_xtempobj These files are: - add-ed at revision 0, and - edit-ed at revision 1 According to perforce command reference below, file type 'tempobj' and 'xtempobj' imply '+S' modifier, which indicates that "Only the head revision is stored". This means that these files should appear only in the most recent revision (= revision 1). https://www.perforce.com/perforce/doc.current/manuals/cmdref/file.types.html BTW, test-convert-p4-filetypes.t with 2015.2/1366233 version of p4/p4d fails similarly also at recent revisions for hgext/convert/p4.py in 2015. Therefore, this patch should be reviewed by perforce guru, to examine whether this failure depends on version (and/or configuration) of p4/p4d or not.

crecord: re-enable reviewing a patch before comitting it The "r" option for this feature was copied into Mercurial from crecord, but the actual implementation never made it into hg until now. It's a moderately useful feature that allows the user to edit the patch in a text editor before comitting it for good. This requires a test, so we must also enable a corresponding testing 'R' option that skips the confirmation dialogue. In addition, we also need a help text for the editor when reviewing the final patch. As for why this is a useful feature if we can already edit hunks in an editor, I would like to offer the following points: * editing hunks does not show the entire patch all at once ** furthermore, the hunk "tree" in the TUI has no root that could be selected for edition * it is helpful to be able to see the entire final patch for confirmation ** within this view, the unselected hunks are hidden, which is visusally cleaner ** this works as a final review of the complete result, which is a bit more difficult to do conceptually via hunk editing * this feature was already in crecord, so it was an oversight to not bring it to core * it works and is consistent with editing hunks