rax module: improvements

Adding support for detecting RHEV Hypervisor in ansible_virtualization_type

While looking into filters, I noticed that the documentation has a typo....

Fixes #5513. set is built-in since 2.4 and deprecated since 2.6

Modified docsite layout to use Google custom search.

Synchronize Module: Improved sudo override behaviour.

ec2 modules: Move more responsibility to common EC2 module

file module: Fixed missing prev_state == 'directory' in file

ec2 inventory: Fail EC2 inventory better with restricted EC2 users

Allow multiple users to use ec2 inventory scripts

This may still be an issue if users create roles with a '.' in the name though.
We will probably have to disallow that in the role naming convention.

https://github.com/ansible/ansible/pull/5251

Fact gathering on a second play against the same hosts should not be implicitly off since this is an undocumented beheavior and potentially
rather unwanted when a play could change a fact.

gather_facts: True/False can still be explicitly used per play.

Reverts 564a212b

fix issue #5372 on ssh_alt: accept -K option for a user with NOPASSWD

Use "brew list <name>" instead of grepping the output of "brew list". Fix for #5488

Return early from setup step when possible

For loops can be inefficient, particularly when doing a dot command with
them. https://wiki.python.org/moin/PythonSpeed/PerformanceTips#Loops and
https://wiki.python.org/moin/PythonSpeed/PerformanceTips#Avoiding_dots...

This patch makes use of list comprehensions to be as efficient as
possible while still retaining order. Efficiency was lost a bit when
switching away from sets() but this gains some of it back.

Fixed typo in example documentation

The _list_available_hosts call can be lengthy, and in the case where
gather_facts is disabled the call is pointless. So re-arrange the logic
to return early from _do_setup_step when gather_facts is false.

Remove code underlying when_* and only_if, which are deprecated features slated for removal in the 1.5 release.

Resolves issues with newer versions of pip not having a --use-mirrors paramater for the install command

We have had only_if, when_foo, etc, deprecated for a while and said they would be removed in 1.5.  Now they are, with friendly error messages still.

Users of these features should use "when:" as documented at docs.ansible.com.

Similarly, include + with_items has been removed.  The solution is to loop
inside the task files, see with_nested / with_together, etc.

build manpages.