Python-base-app

* Use new CSRF handling

* Closes 12, see [here](https://github.com/marcus67/python_base_app/issues/12)

* Moved `copy_attributes` and `create_class_instance` from LittleBrother to `tools.py`
* Added method `compare_objects` in `tools.py`
* Moved `check_list_length` from LittleBrother to `base_test.py`
* Added support for SonarQube analysis (script generation)
* Read `.dev-env-settings.sh` in `test-app.sh`
* Don't assume `BaseWebServer` to have a blueprint
* Show version details for Chrome/Selenium test environment

* Make test suite compile on MacOS

* Add Debian packages in `python_base_app/templates/debian_control.template.conf` to enable loading
of Python module `python-ldap`

* Move functionality from `UnixUserHandler` to `BaseUserHandler`

* Add new class `LdapUserHandler` for authorization and authentication with an LDAP server

* Exclude template Python files `.coveragerc`

* Repair call of `coverage`

* Add test cases for class `UnixUserHandler`

* Add test case for health API
* Add babel-login to requirements.txt (triggered by new test case)
* Add dependency on package `some_flask_helpers`
* Add helper function `get_dns_name_by_ip_address()`