Added tasks to copy the app and ossec alert gpg key public keys to the remote host since production will not be using vagrant

Removed the word 'path' from the the variable names for the app/ossec gpg key and the custom header image variables since it does not a path anymore.

The custom header image, app gpg public key, ossec gpg public key and the smtp's CA cert need to be either in the install_files/ansible-base directory or the respective role's file directory
Added a unique test gpg keypair since in production these would also be two separate keypairs.

The application's gpg private key is airgapped, while the admin's gpg private key is on their networked work machine so they are able to decrypt the emails.
GPG is being used for the OSSEC alerts to protect them in the event that the organization email server is compromised.
Add Python-RQ worker and make sure it's started when needed
added a check to see if the OSSEC archive already exists and if it does exist then skip downloading it again.
moved defining the generic ossec variables from the app/mon host_vars to group_vars.
Auto-start an rqworker for manage.py tasks that need one
Enqueue potentially time-consuming secure unlinks
Test that deleted files are actually removed from the filesystem

The tests use a polling wait since deletion is handled by a polling
worker, and secure deletion can be time consuming. At the moment, the
test files are all very small, so they secure delete quickly. The added
overhead is < 1 second.

This increases test coverage as well - previously, we were not testing
that deleted files were actually removed from the filesystem.
Add debugging for intermittent (very infrequent) scrypt error
Ansible playbooks set up supervisor to run job queue worker
Use separate job queue for jobs from manage.py test

Python-RQ is nice because it lets us schedule jobs that are arbitrary
Python functions. The downside is that, due to our messy "config as a
module with values derived from an environment variable" setup, there
can be issues. For example, jobs sent from the tests will not run
correctly on the default worker (started by supervisor), because they
were started with different values for SECUREDROP_ENV and therefore have
different SECUREDROP_ROOTs.

Clearly this whole situation needs to be improved but this hack is
reasonable and works well for now:

1. Use a separate "test" queue for jobs triggered by the tests
2. Start/stop a temporary "test"-queue-only rqworker for the tests
Increase memory allocation for development VM

Functional tests have recently been failing due to "out of memory"
errors. My theory is that this is due to the new release of Firefox,
which came out two days ago (and usually takes a day or so to make it
into the mainline repos) using more memory than the previous release.
Timelines match up, although I haven't done any further testing to prove
this.

Nice side effect: increasing the amount of available memory makes
Firefox run faster, which makes the functional tests run faster. Also
appears to eliminate various intermittent errors from the functional
tests, such as the "empty status line" error from Selenium and the
TypeError from python-gnupg. This makes sense!
Fix Travis builds

For some reason, redis-server does not start automatically after it is
installed on Travis. *shrug*
During one of the last merges I broke the procmail and the ossec sasl_password configuration. This fixes that.

Removed the .procmail file from being packaged with the ossec-server deb package. This was causing ansible not to reload postaliases.

Migrated the 'postalias /etc/aliases' and 'postmap /etc/postfix/sasl_passwd' task to a handler.

Changed the way that ossec alert gpg keyring is created so that it doesn't cause issues on subsequent runs and removed the warning comments about it.

Removed the unneeded backslash in the send_encrypted_alarm.sh.

Added creating the .gnupg directory in the OSSEC server's deb package postinst to avoid permission issues.
Ansibles stat module only supports checking the md5 sum of the file.
But did and that verification to the check to see if the ossec archive already exists

http://docs.ansible.com/stat_module.html
changed all the tabs to spaces
Merge pull request #645 from dolanjs/gpg-key-without-vagrant-fix

Copy the app and ossec alert gpg key to remote host
Merge pull request #646 from dolanjs/check-for-ossec-download

Check for ossec download
Merge branch 'fix-sending-ossec-alerts' of https://github.com/dolanjs/securedrop into dolanjs-fix-sending-ossec-alerts

Conflicts:
	install_files/ansible-base/roles/mon/tasks/mon_configure_ossec_gpg_alerts.yml
Merge pull request #647 from freedomofpress/task-queue

Task queue