stack: use stack._revs instead of stack.revs[1:] in external children revset
The revset in question excludes all revs that are part of the stack. Using
stack.revs[1:] works (rev #0 is stack base, which is not a part of the stack),
but using stack._revs is technically more correct, because this variable is
specifically designed to hold only revisions that are part of the stack.
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.