Update inline docs for catalog parsing
Update inline docs for catalog parsing

Slight reformatting of content; the marginalia docs talk about code-related
constructs, and we link to the spec when we're discussing wire-format
constructs.

Signed-off-by: Deepak Giridharagopal <d11186354d1ef01ca06ae37d7e23e827da13e85f@puppetlabs.com>

stahnma/puppetdb,waynr/puppetdb,nfagerlund/puppetdb,puppetlabs/puppetdb,wkalt/puppetdb,puppetlabs/puppetdb,rbrw/puppetdb,jantman/puppetdb,shrug/puppetdb,puppetlabs/puppetdb,kbarber/puppetdb,rbrw/puppetdb,kbarber/puppetdb,github/puppetlabs-puppetdb,jantman/puppetdb,cprice404/puppetdb,rbrw/puppetdb,waynr/puppetdb,nfagerlund/puppetdb,highb/puppetdb,melissa/puppetdb,grimradical/puppetdb,haus/puppetdb,wkalt/puppetdb,mullr/puppetdb,johnduarte/puppetdb,kbarber/puppetdb,johnduarte/puppetdb,rbrw/puppetdb,kbrezina/puppetdb,cprice404/puppetdb,mullr/puppetdb,haus/puppetdb,github/puppetlabs-puppetdb,mullr/puppetdb,puppetlabs/puppetdb,shrug/puppetdb,kbrezina/puppetdb,melissa/puppetdb,grimradical/puppetdb,kbrezina/puppetdb,senior/puppetdb,highb/puppetdb,highb/puppetdb,kbarber/puppetdb,grimradical/puppetdb,mullr/puppetdb,melissa/puppetdb,senior/puppetdb,waynr/puppetdb,nfagerlund/puppetdb,puppetlabs/puppetdb,johnduarte/puppetdb,cprice404/puppetdb,kbrezina/puppetdb,shrug/puppetdb,ajroetker/puppetdb,github/puppetlabs-puppetdb,shrug/puppetdb,highb/puppetdb,jantman/puppetdb,waynr/puppetdb,grimradical/puppetdb,rbrw/puppetdb,senior/puppetdb,stahnma/puppetdb,senior/puppetdb,wkalt/puppetdb,johnduarte/puppetdb,ajroetker/puppetdb,mullr/puppetdb,wkalt/puppetdb,haus/puppetdb,ajroetker/puppetdb,ajroetker/puppetdb,stahnma/puppetdb