contrib/docker/centos6

diffstat: properly count lines starting in '--' or '++' (issue5479)

Lines that start in '--' or '++' were previously not counted
as deletions or additions in diffstat, resulting in incorrect
addition/deletion counts.  The bug was present if the start
of the line, combined with the diff character resulted
in '---' or '+++'.

diffstatdata will now track, for each file, if it has moved
pas the header section by looking for a line beginning with
'@@'.  Once that has happened, lines beginning with '-'
or '+' will be counted for deletions and additions.  Once a
line beginning with 'diff' is found, the process starts over.

FROM centos:centos6
RUN yum install -y gcc
RUN yum install -y python-devel python-docutils
RUN yum install -y make
RUN yum install -y rpm-build
RUN yum install -y gettext
RUN yum install -y tar
# For creating repo meta data
RUN yum install -y createrepo