revlog: refactor out _finddeltainfo from _addrevision
Splicing the code into smaller chunks should help understanding it,
and eventually override some parts in experimental branches to try
optimization.
FROM debian:__CODENAME__
RUN apt-get update && apt-get install -y \
build-essential \
debhelper \
devscripts \
dh-python \
less \
python \
python-all-dev \
python-docutils \
unzip \
zip