Add documentation for new event query fields
Add documentation for new event query fields

senior/puppetdb,kbrezina/puppetdb,senior/puppetdb,highb/puppetdb,cprice404/puppetdb,wkalt/puppetdb,wkalt/puppetdb,kbarber/puppetdb,johnduarte/puppetdb,ajroetker/puppetdb,ajroetker/puppetdb,jantman/puppetdb,ajroetker/puppetdb,senior/puppetdb,rbrw/puppetdb,waynr/puppetdb,waynr/puppetdb,jantman/puppetdb,puppetlabs/puppetdb,senior/puppetdb,waynr/puppetdb,cprice404/puppetdb,ajroetker/puppetdb,mullr/puppetdb,shrug/puppetdb,grimradical/puppetdb,rbrw/puppetdb,rbrw/puppetdb,johnduarte/puppetdb,highb/puppetdb,grimradical/puppetdb,shrug/puppetdb,puppetlabs/puppetdb,kbarber/puppetdb,wkalt/puppetdb,kbarber/puppetdb,mullr/puppetdb,kbarber/puppetdb,kbrezina/puppetdb,grimradical/puppetdb,mullr/puppetdb,jantman/puppetdb,wkalt/puppetdb,mullr/puppetdb,mullr/puppetdb,grimradical/puppetdb,kbrezina/puppetdb,rbrw/puppetdb,johnduarte/puppetdb,highb/puppetdb,highb/puppetdb,johnduarte/puppetdb,waynr/puppetdb,rbrw/puppetdb,shrug/puppetdb,kbrezina/puppetdb,puppetlabs/puppetdb,cprice404/puppetdb,puppetlabs/puppetdb,puppetlabs/puppetdb,shrug/puppetdb