rebase: add --stop option to stop rebase at any point (issue5206) Before this patch, during a rebase if you get a point where you can't figure out what to do next, then either you had to complete your series or abandon all the work you have done during this rebase. Now, with this feature you can stop at any point by keeping the rebased csets and mark original csets as obsolete. And if you don't have evolution extension enabled then you can use --keep option as an alternative which will keep original csets too, instead of marking them obsolete. Differential Revision: https://phab.mercurial-scm.org/D3959

statprof: cleanup string construction Use string substitutions instead of string additions.

addremove: add associated color for the new labels We use classic color: green is added, red is removed.

remove: add a label for messages about removed files Keeping consistency between addremove and remove seems a good idea.

add: add a label for messages about added files Keeping consistency between addremove and add seems a good idea.

addremove: add labels for messages about added and removed files This is the first step to add color for add and remove output.

revlog: filter out "invalid" delta base candidates There are bases that we know won't produce a good delta chain. For example, if the base is already bigger than twice the size of the text we store, we know the resulting delta chain will never be valid. We might make the check a bit more powerful and generic in the future, but this looks a good start. In particular, empty file (size 0) will never find a good base, so we should stop spending time trying to find one.

revlog: use a symbolic constant for the deltas/text ration We are about to use it somewhere else, we should as well make it easier to access and change.

revlog: do not search for delta for empty content We won't find any useful base to store an empty text. So we should not even try to.

revlog: split and document good delta conditional The logic is still identical, but having each conditional on its own helps to document them and will help to edit them in the future.