COOK-3021 Proper resource update
add attribute for optional intermediate ssl certificate
add attributes for pagerduty contact's service_notification_options and host_notification_options
Add more tunable directives for default host

Adds `check_period`, `check_command` & `notification_options` attributes
for tuning the default host template. Also added a bunch of docs for the
`node['nagios']['default_host']` attributes.
single quotes make rubocop a happy robot
sort hostgroups so they don't get updated on each run
Allow multiple hostgroups to be specified in a services block.
Add customization points for Icinga cookbook
Don't reuse resource names.
Use correct source for main config
Unify pagerduty script name
rubocop
[COOK-3723] Support regexp_matching in Nagios
remove empty line, thanks tas50
Merge pull request #173 from mpasternacki/COOK-3287

[COOK-3287] Add customization points for Icinga cookbook
Update nagios plugins to the latest URL to fix broken RHEL NRPE and
nagios installs
Fix incorrect server packages

Nagios failed to install on Debian/Ubuntu.  Nagios should be Nagios3.  Found and confirmed via Test Kitchen
Clarify the new attribute for server and vname for icinga installs
Merge pull request #200 from tas50/master

[COOK-3729] - Update nagios plugins to the latest URL to fix broken RHEL NRPE installs
Drop TK memory allocation for clients from 1024 -> 512

Tested that this is still enough to compile the NRPE client.  No need to allocate more than that since some people only have dev systems with 4GB ram.