Customize installed Apt packages

[nathanielks]

This adds a few new variables:

• apt_packages_default
• apt_packages_custom
• apt_packges_install

If a user wishes to install additional apt packages, they simply need to add items to the custom_apt_packages variable:

apt_packages_custom:
  - nfs-utils

[retlehs]

• default_apt_packages -> apt_packages_default
• custom_apt_packages -> apt_packages_custom
• install_apt_packges -> apt_packages_install

[swalkinshaw]

you snuck some of your custom ones in here

[swalkinshaw]

Looks good 👍 Can you add changelog entry?

[hamedb89]

I am having problems with this commit.

TASK [fail2ban : ensure fail2ban starts on a fresh reboot] *********************
System info:
  Ansible 2.0.2.0; Vagrant 1.8.6; Darwin
  Trellis at "Add `apt_packages_custom` to customize Apt packages"
---------------------------------------------------
error importing module in /usr/local/lib/python2.7/site-
packages/ansible/modules/core/system/systemd.py, expecting format like 'from
ansible.module_utils.<lib name> import *'
fatal: [default]: FAILED! => {"failed": true}

NO MORE HOSTS LEFT *************************************************************
	to retry, use: --limit @/Users/hamedbahrami/vagrant/design-factory.de/trellis/dev.retry

PLAY RECAP *********************************************************************
default                    : ok=6    changed=0    unreachable=0    failed=1   

Ansible failed to complete successfully. Any error output should be
visible above. Please fix these errors and try again.