This CL, inspired from https://golang.org/cl/16911, drops the use of
`x/tools/go/loader` (importing from sources) and replaces it with the stdlib
`go/importer`, working off the (binary) exported data under
$GOPATH/pkg/pkgname.a.
This allows us:
- to rely completely on the stdlib-1.5,
- to support cgo-based packages (which are not supported by `x/tools/go/loader`)
Fixes#28Fixes#36Fixes#68Fixes#70
Change-Id: I0321645dfeec8738687a675a7e80283053c89123
Sebastien Binet