task: add index number to the output We are doing to use these number for easy movement in later changesets. The numbering will probably evolve over time but this is a good start.

stack: fix printing order in case of unstability The stack was displayed using revision number order, this give good result in the simple case (straight stack) but give bad result when the stack is not linear because of unstability. We fixes it by reusing the evolution logic for sorting. As we do not live next to evolution yet, we duplicated this logic for now.

stack: exclude obsolete changeset from the set We care about relevant changeset, obsolete have a new version somewhere and we don't care about the old one in our display. In case of unstability, the ordering used is still wrong.

stack: add a very first version of stack display with 'hg topic --list' This mark the first step toward a set of feature dedicated to displaying and moving within the current stack of work. Everything is still super basic so don't look too much at the feature. The goals of this changeset are: * having a flag to trigger the feature * having a basic (imperfect selection mechanism)

topic: get 'Abort' from error, not 'util' The class live in 'mercurial.error'.

Makefile: meant tests-@ not tests-tip