Use the exact formatting suggested in COPYING file.
This change is basically a pretext to trigger a new clean build in
order to check if Coverity is capable of accepting new builds for
analysis finally.
Some distributions provide python2 version of pylint package by default,
but all provide pylint for python3 in some package. Python 2 reaches
EOL in few months, so there's no reason to support it.
This prevents our scripts from being accidentally marked invalid due to
language changes between python 2 and 3. Also, newer pylint has nicer
output, that provides exact module filename straight in the warning.
Includes two small scripts: verify-bash.sh for running shellcheck, and
verify-python.sh for running pylint.
.pylint rc files is a default configuration file generated by
pylint 2.3.1, with one change (min-similarity-lines changed
from 4 to 10).
