GC-28: Added initial set-up for running tests within Vagrant machine:

- Added Vagrantfile that deploys Debian 9 Stretch and provisions it.
- Added provisioning script that will set-up multiple Python versions.
- Updated development instructions to include information on how to
use Vagrant to run all the tests.
- Ignore Vagrant artifacts in gitignore.

GC-20: Implemented status command for initialised directory:

- Added functional test.
- Implemented showing CA hierarchy, server and client certificate
information for initialised directories.
- Implemented helper functions for generating string representation of
DNs, DNS subject alternative names, and date range.
- Return correct error when calling status command on uninitialised
directory.
- Updated gitignore to exclude *.pyc from repository.
- Implemented unit tests.

GC-2: Added tox configuration:

- Configured multiple environments for running tests against Python
3.4, 3.5, and 3.6.
- Configured environment for running linting tests.
- Configured environment for running documentation builds.
- Updated requirements for running linting tests.
- Updated pytest configuration to include running linting tests.
- Updated gitignore to exclude tox artefacts.

GC-2: Added coverage configuration and updated manifest file:

- Include only the actual module files in the coverage reporting.
- Addd comments to gitignore file.
- Updated gitignore file to exclude test artefacts.
- Updated manifest file to include documentation files, as well as
test configuration file.
- Added pytest configuration file that ensures coverage plugin is
enabled and that report is stored in html format in the coverage
directory.

GC-2: Added initial package setup configuration:

- Updated gitignore to exlude some of the build and Python artefacts.
- Added manifest file, including a number of files that are not
normally being distributed.
- Created setup.cfg that overrides default command for running tests.
- Added initial setup.py.

GC-2: Adding initial documentation skeleton with some basic information about the project:

- Added basic documentation describing the project.
- Updated gitignore file to ensure documentation build artifacts stay
out of the repository.
- README file placed at top directory for convenient access.