ewaol-config/tools: Add python and shell code check script

codecheck.py is a script that finds all shell script files with given tree,
and runs shellcheck on all files that are not in excluded list.
It also runs pycodestyle check for all python files,
within the same directory tree.

This code check script is using venv to isolate required packages,
from user environment. After check is finished, created venv is deleted.
Logging can be changed with '--log' option,
three log levels are available: warning(default), info and debug.

Sample usage:
  $ meta-ewaol-config/tools/codecheck.py . --exclude tools

Issue-Id: SCM-2586
Signed-off-by: Kamil Dziezyk <kamil.dziezyk@arm.com>
Change-Id: I21289169b07b3d9ec590075b08fb32554a81ff36