OPS-1593 As an operator, I want sudo_user converted to become user in roles and plays, for compatibility with Ansible 2.x

OPS-1593 As an operator, I want sudo_user converted to become user in roles and plays, for compatibility with Ansible 2.x

OPS-1593 As an operator, I want sudo_user converted to become user in roles and plays, for compatibility with Ansible 2.x

I removed this in 9ae2caa0 so it's a no-op

* add splunk searches via ansible

* Fix jinja syntax, add docs

* Add splunk field extractions via ansible

* Use a boolean rather than a number

The fact that splunk uses "1" and "0" to represent booleans is
orthogonal to booleans in yaml. Switching to true booleans for a better
user experience.

* Additional cleanup around splunk searches interface

* Switch splunk role to using common_vars and overrides

This way, we can support environments where we don't, for example, use
datadog.

* Make splunk playbook actually call splunk role

* Fix all the bugs

* Add splunk email config

* Make realtime alerts work

* Add more documentation around splunk alerts

* Address comments

We now run this script places other than us-east-1 and we use the
box's IAM role rather than a profile.

Seems like we stopped using devpi with #971 two years ago.

If a git version is specified as a branch, and the commit referred to is
already on the local working tree, but the branch is not, then the
checkout will fail.

This is because the Ansible 1.9.3 module would check to see if the
commit was already present, and if so, did not fetch. This meant the
branch wasn't defined in the local working tree.

This can happen if you make a branch but there aren't any changes on the
branch.

Does so by running the edxapp role just to generate config (as
controlled by check-migrations.sh's use of the --tag) and then
the tasks in the playbook are hardcoded to always run, regardless
of the tag.  Because the edxapp play has run, the tasks have
access to the various config variables containing DATABASES
and can tell what DBs are in use.

Skip the read replica

Django 1.8 removed the syncdb command so we can no longer run it, don't
imply that we are running it in documentation/messages, also don't
provide the scripts used on devstack/sandboxes to run it since they'll
never work anyway.

Additionally - remove yet another openid workaround which is unnecesary
since the Django 1.8 upgrade.

The "connection: local" option prevented us from running the playbook on
another host (e.g. an app server) which gets around security
restrictions on connecting to DB servers. Also, the option is totally
unnecessary. There's no reason this play couldn't run remotely.

Previously on this branch, it would attempt to create a superuser and
initialize the replica set after the local host exemption had passed
(once a mongod is started with a keyfile and the replicationSetName
 config file option or --replSet command line argument, you can't create
 users using the localhost exemption anymore ).

This necesarily complicates the logic and requires us to track if we're
initializing a replica set or not (with facts) and to template out
/etc/mongod.conf twice in the initialization case.

Further modifications to the replica set can be run against all the
members and will install mongo on new machines while updating the
replica set on the old machines.  With a further commit on this branch,
we can avoid needlessly restarting mongo on all machines in the cluster.

When we run this on an existing cluster, this stops and starts mongo for
all machines it is run against.  We can't rely on the notify: since that
happens at the end of the play and during initial cluster setup, we need
to restart and pick up the changed config.

Try to stick sensible tags on things

Ensure mongo restarts on the cluster key file change

Add a few playbook notes about common operations

Remove check for mongo 2.4 since this is the mongo_3_0 role
This was probably carried over from the mongo 2 role. I see no reason
why mongo 2.x and mongo 3 couldn't coexist on the same machine.

Remove old hugepages init script check
This was probably added while we were still iterating on our mongo 3
deployment, but it should no longer be necessary.

Clean up ansible syntax

Don't move the old mongo data dirs
This actually skips for edX because we provision machines that already
have {{mongo_data_dir}} mounted on an external disk.  However, for
non-edX use, this could fail if you turn on WiredTiger since it will
move mmapv1 files into the mongo_data_dir and then mongo will fail to
start because it has been told to use WiredTiger.

Don't make this a serial play
We usually run this on 3 machines, so serial: 3 was equivalent to
ansible's default of "run everything in parallel" but this causes
problems if you ever run it on 4 like we do for prod envs.
In addition, this prevents run_once from working properly, and there are
a number of things we only one to do on one machine (like creating a
superuser).

Add usage example to alton playbook
Allow alton to use most recent redis version
HEAD is a local-specific value. Instead, we should check out master.

ECOM-3181

refactoring common inclusion based on comments

removing motd template from common

Removing sshd template

relocating temlates

relocating templates

Relocating dhclient templates

explicit play depends

Update responsibilities

indent

further dependency updates

additional updates

Common dependency for server utils

Supervisor is required for role integrity

Typos

further template ownership changes