go: reorganize the go bindings

go 1 introduced the "go" program that simplifies building of libraries
and programs. This patch reorganizes the go code so it can be compiled
using the new utility, it does not change any files.

Signed-off-by: Justus Winter <4winter@informatik.uni-hamburg.de>

diff --git a/bindings/go/cmds/notmuch-addrlookup.go b/bindings/go/src/notmuch-addrlookup/addrlookup.go
similarity index 100%
rename from bindings/go/cmds/notmuch-addrlookup.go
rename to bindings/go/src/notmuch-addrlookup/addrlookup.go

diff --git a/bindings/go/pkg/notmuch.go b/bindings/go/src/notmuch/notmuch.go
similarity index 100%
rename from bindings/go/pkg/notmuch.go
rename to bindings/go/src/notmuch/notmuch.go