(PDB-728) Update release notes for 2.1.0
(PDB-728) Update release notes for 2.1.0

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