database/sql: more tests
database/sql: more tests

Higher level tests for the pointer parameters
and scanning, complementing the existing ones
included in the previous CL.

R=golang-dev, dsymonds
CC=golang-dev
http://codereview.appspot.com/5646050

apparentlymart/golang,apparentlymart/golang,apparentlymart/golang,gnanderson/go,gnanderson/go,pombredanne/go-deleteme,tv42/old-go,dsriram/golang,gnanderson/go,tv42/old-go,gnanderson/go,gnanderson/go,pombredanne/go-deleteme,dsriram/golang,pombredanne/go-deleteme,pombredanne/go-deleteme,dsriram/golang,dsriram/golang,pombredanne/go-deleteme,gnanderson/go,dsriram/golang,tv42/old-go,apparentlymart/golang,dsriram/golang,apparentlymart/golang,tv42/old-go,pombredanne/go-deleteme,apparentlymart/golang,pombredanne/go-deleteme,tv42/old-go,dsriram/golang,apparentlymart/golang,tv42/old-go,tv42/old-go,gnanderson/go