Added module to handle rabbit policies [1]

Used quite a bit of the existing rabbit modules provied by @chrishoffman.

[1] https://www.rabbitmq.com/parameters.html
Cleaned up docs just a smidge

Mostly added periods where missed, and corrected /vhost spacing.
The setting of params via dict or string by tags

Updated per @mpdehaan suggestions.
* Rather than passing in JSON, supply the policy options as a hash
  or string.
* Bumped version_added to 1.5.
Handled string/dict the ansible way
Added existing_only options to skip creating new files on receiver
Added -FF flag to rsync invocation in synchronize

The `-FF` option causes rsync to look for files in the source directory named `.rsync-filter` and uses them to filter directories underneath them. If no `.rsync-filter` files are found, the behavior is identical to the command run without the -FF option. This flag does not sync the .rsync-filter files themselves.

This change should be backwards compatible and not produce surprising behavior for users, since they are unlikely to create `.rsync-filter` files unintentionally.
Added note about .rsync-filter files, with example
Fixed a typo.
Added version_added
now handles default and allaows for either shorthand entry or specific
fields per entry section

the default option works both when added to entry or as stand alone.
Signed-off-by: Brian Coca <briancoca+dev@gmail.com>
rds module: add snapshot capabilities

Add the ability to create snapshots and restore from them
Make instance creation, deletion, restore, and snapshotting idempotent
(really helps testing a playbook if you can run it multiple times)
Downgraded module version_added.
path_dwim: fix when basedir not set
Use /etc/rc.conf.local for sevice configuration on FreeBSD

/etc/rc.conf.local is the preferred location for system-specific
startup configuration, and /usr/local/etc/rc.conf generally isn’t used.

see:
http://www.freebsd.org/doc/handbook/configtuning-core-configuration.html
keep /usr/local/etc/rc.conf for backwards compatibility
fixed bug causing symlinks to fail in the host_vars, group_vars etc directories
Enable changes to ttl of a record to be propogated to route53
PlayBook: better error message

When a PlayBook has missing arguments the error message now shows which ones are missing.
Fix multiple minor typos in a paragraph

Add missing word, remove extraneous word, move misplaced quote,
switch single quotes to be double quotes for consistency in a
single paragraph.
added new play_hosts var

this variable has the 'current host list' to be executed over in the
play. Useful when using --limit to not iterate over hosts not included
in play in templates or with_items.

Signed-off-by: Brian Coca <briancoca+dev@gmail.com>