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
Downgraded module version_added.
Add support for --copy-links
Fix slow ssh

We break the read while loop after waiting "the end of the process" and
the pipes are empty, otherwise we do another select that waits all the
timeout.
Fix missing quote mark in route53 doc example
Merge pull request #5882 from amirhhz/patch-1

Fix missing quote mark in route53 doc example
Merge pull request #5187 from 42wim/devel

Add support for --copy-links in synchronize
Merge pull request #5879 from lberruti/ssh_slow_fix

Fix slow ssh
Merge pull request #5127 from ovcharenko/patches

synchronize module: Added existing_only options to skip creating new files on receiver
Merge pull request #5051 from deontologician/patch-1

Added -FF flag to rsync invocation in synchronize
When force=yes, get_url should always download the specified file

This is accomplished by not setting the If-Modified-Since header,
and setting "cache-control: no-cache" instead. Note that if the
file content has not changed, the module will still report that
changed=false, as the md5's of the tmp file and existing file are
compared before swapping

Fixes #5104
Clarify doc for get_url

Move a sentence from doc for the "force" option to that for the "dest" option.