Minor readme cleanup
Minor readme cleanup

Capitalize Nagios and NRPE
Use a single space after periods
Fix a few minor typos and add commas

Piousbox-cookbooks/nagios,schubergphilis/nagios,polamjag/nagios,OpenGov/nagios,CanaryTek/nagios,CanaryTek/nagios,spudnic/nagios,ovaistariq/nagios,spudnic/nagios,earzur/nagios,firebase/nagios,polamjag/nagios,OpenGov/nagios,mrlamroger/nagios,mrlamroger/nagios,OpenGov/nagios,CanaryTek/nagios,mrlamroger/nagios,spudnic/nagios,ChrisLundquist/nagios,Piousbox-cookbooks/nagios,schubergphilis/nagios,schubergphilis/nagios,ovaistariq/nagios,popsikle/nagios-5.3.5,JulianNL/nagios,bitmonk/chef-nagios,caleb/nagios,bitmonk/chef-nagios,aaronkvanmeerten/nagios,earzur/nagios,firebase/nagios,earzur/nagios,firebase/nagios,ChrisLundquist/nagios,caleb/nagios,bitmonk/chef-nagios,mrlamroger/nagios,ChrisLundquist/nagios,ovaistariq/nagios,polamjag/nagios,OpenGov/nagios,spudnic/nagios,Piousbox-cookbooks/nagios,JulianNL/nagios,popsikle/nagios-5.3.5,JulianNL/nagios,bitmonk/chef-nagios,Piousbox-cookbooks/nagios,firebase/nagios,aaronkvanmeerten/nagios,JulianNL/nagios,aaronkvanmeerten/nagios