Set keepalive to 5 seconds in paramiko_ssh.py

This update resolves https://github.com/ansible/ansible/issues/6476.
Improve the ec2_snapshot argument spec and docs

ec2_snapshot got missed when moving to a common argument spec.
It could already make use of the capabilities (as it uses
ec2_connect) and the documentation suggested it supported the
common argument spec (thanks to the documentation fragment work)
so it was just a matter of fixing the argument spec.

Removed unnecessary documentation for profile and security_token
that is covered by documentation fragment

Also removed spurious documentation flags (default: null, aliases: [])
which aren't needed.
if key name already exists on tenant, check if public_key is offered that it matches the existing key
Fixed incorrect handling of paths contaiin whitespaces
Enable use of vault password for --syntax-check, --list-hosts and --list-tasks
Added integration tests for encrypted vars
Enabled integration tests for encrypted vars in Makefile
Fix neutron floating IP allocation for networks with a v4 *and* v6 subnet.

For networks that have both a v4 and a v6 subnet, the floating IP plugin
currently has two problems:

* When determining the subnet for the provided `internal_network_name`, it
assumes that the first item in the list of subnets is the one you want.
Instead, it should pick the first v4 subnet.

* When multiple fixed IP's exist for a given port (as is the case in a network
a v4 and a v6 subnet), neutron needs a hint as to which fixed IP to associate
to the floating IP address (the v4 one).
Add environmentfilter to random filter, to ensure the result doesn't get cached. Mirrors default jinja filter.
Fix incorrect argument ordering in error message, which provokes a
printf-related TypeError.
Merge pull request #7705 from smoothify/random-nocache

Ensure random jinja filter doesn't get cached in loops.
Merge pull request #7707 from rrgomes/devel

Fix incorrect argument ordering in error message
Merge pull request #6507 from brdo/patch-1

Set keepalive to 5 seconds in paramiko_ssh.py
Merge pull request #7238 from willthames/ec2_snapshot_argument_spec

Improve the ec2_snapshot argument spec and docs
Merge pull request #7259 from darKoram/nova_keypair_check_keys

nova_keypair should fail if 'name' of key exists in keystore, but ssh hash value != public_key offered
Merge pull request #7377 from mikhailguru/devel

Fixed handling of paths containing whitespaces in the synchronize module
Docker links and required alias

If no alias is passed one will now be created for you with the same name
as the target link container, as per the documentation
Merge pull request #7714 from pmyjavec/devel

Docker links need alias specified
Merge pull request #7687 from ryanpetrello/devel

Fix neutron floating IP allocation for networks w/ multiple subnets
Back-porting 1.6.x release info into CHANGELOG/RELEASES and packaging