docs: add two more amend commits to simulate temporary amend commits sharing.rst made reference to temporary amend commits and used them to demonstrate that hidden commits are not exchanged. Nowadays, evolve doesn't create such commits, but it still makes sense to show how they are handled during the exchange process. So let's add two more amend commits, one for each repo. This way the guide doesn't have to be updated too much, but doesn't lose this important detail of working with evolve. Unfortunately, this means that tons of hashes change, but it's better than to have figure 4 demonstrate absolutely nothing. Temporary amend commits were removed from test-sharing.t in 06844693bb21, but sharing.rst continued using them for demonstration purposes. It might've been better to replace at least some of the temporary amend commits by extra amends back then, but oh well.

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.