evolve: make sure divergence resolution doesn't undo changes (issue6203) Before this patch, in content-divergence resolution logic if resolution parent is not the parent of any of the two divergent changesets then it could undo some changes introduced by previous revs (while resolving stack of content-divergent changesets) as demonstrated by the test added in previous patch. To solve this, what this patch doing is: if divergent cset has obsolete parent with a successor then first resolve the "orphan" instability of divergent cset by relocating, then perform the content-divergence resolution. After this change in logic, I found that it's kind of more correct as reflected by the changes in tests/test-evolve-content-divergent-corner-cases.t where it prevented creating conflicts while merging. Changes in tests/test-evolve-content-divergent-stack.t demonstrate the fixed behaviour. Next patches will be covering the `evolve --continue` case for the relocation of "divergent" cset.

Doc is generated with sphinx.

You can generate the doc with:

```
make
```

# Tutorials

For updating the tutorials, you need to have the docgraph extension installed
(https://pypi.python.org/pypi/hg-docgraph).

Then run the test-topic-tutorial.t and test-tutorial.t to update the output if
needed.

You'll need the dot binary (likely installed by the graphviz package in your
package manager) in order to have graphviz graphs rendered in the html output.

Simply run make in the docs directory should takes care of the conversion of
the tutorial .t files into .rst files. Then sphinx should do the rest of the
jobs by rendering graphviz graphs.