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

h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang