- include type-associated consts and vars when filtering a PackageDoc - fixes a godoc issue (for instance, "godoc os EOF" now shows an entry)
- include type-associated consts and vars when filtering a PackageDoc
- fixes a godoc issue (for instance, "godoc os EOF" now shows an entry)

R=r
CC=rsc
http://codereview.appspot.com/165042
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go