doc/go1.2.html: pre-emption; cgo and C++
doc/go1.2.html: pre-emption; cgo and C++

These were bullet points that I had neglected to flesh out.

R=golang-dev, dvyukov
CC=golang-dev
https://codereview.appspot.com/13816043

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