Enable listening on specific interfaces
If you wish for ntp to listen on specific interfaces, instead of leaving it to the daemon's defaults, then:
1) either set the environment/node attribute ["ntp"]["listen"] to the specific value you want it to be
2) or set the environment/node attribute ["ntp"]["listen_network"] to one of the following:
    - "all"       sets the daemon to listen on "0.0.0.0"
    - "localhost" sets the daemon to listen on "127.0.0.1"
    - "primary"   sets the daemon to listen on node["ipaddress"]
    - a CIDR like "192.168.4.0/24" will set the daemon to listen on any server address found that matches that CIDR
Remove unnecessary logging
[COOK-3651] Refactor and standardize cookbook

- Added test for ntp.conf contents to verify_installed.bats.
- Cleaned ntp.conf.erb for readability & indentation.
- Refactored the per-platform settings in the default attributes file to minimize the number of attribute changes.
- Switched per-platform attribute case statement to use platform_family. As part of this change, switched default service name string to 'ntpd' instead of 'ntp', updated unit tests accordingly.
- Ensured that Linux hosts would not try to run the windows_client.rb recipe.
- Ensured that Windows hosts would not try to run the undo.rb recipe.
- Updated the README.md for completeness & clarity.
- Renamed CONTRIBUTING to CONTRIBUTING.md.
- Quick update to metadata.rb to add xcp (RHEL variant) to supported OS list. See GH pull request #14.

Signed-off-by: Seth Vargo <sethvargo@gmail.com>
COOK-3636 Allow ntp cookbook to update clock to ntp servers

Adds two new boolean attributes:
node['ntp']['sync_clock'] - When true, this attribute forces the ntp daemon to halt, executes ntpd -q, and then starts the ntp daemon again. This will repeat every Chef run while the boolean remains true.

node['ntp']['sync_hw_clock'] - When true, this attribute runs the command hwclock --systohc on supported operating systems, forcing the hardware clock to sync to the system time. This will repeat every Chef run while the boolean remains true.
COOK-3636 Added tests & clarified README.

COOK-3636 Added tests for new attributes & clarified README.
Update metadata.rb formatting
Version bump to v1.5.0
Version bump to v1.5.1
Simplify listen_network wrapper and add README note
Fix README merge conflict
Improve CIDR interface search, fix rubocop errors, correct README
Added unit tests for COOK-3604
[COOK-1170] Add a note about why the NTP servers are empty
Fix minor rubocop violation
COOK-3797 - Updated Chefignore file to ignore spec directory.
Merge pull request #35 from charlesjohnson/master

COOK-3797 - Updated Chefignore file to ignore spec directory.
Version bump to 1.5.2
Ensure that ntp['listen'] always beats ntp['listen_network'] if set
Merge pull request #29 from odyssey4me/more-secure-listen

[COOK-3604] Enable listening on specific interfaces
Author: Scott Lampert <scott@lampert.org>
- Add fix for ntp.leapseconds apparmor error
  Fixes [COOK-3023]