test: prepare test for core changeset 9c78ed396075
New changeset in mercurial 2.8 (9c78ed396075) change rebase behavior to preverse
the original working directory. This break an handfull of test so we
preventively update to tip after rebase.
doc generated with sphinx. tutorial exported using sphinxedhghttp://hg.piranha.org.ua/sphinxedhg/