Disable s3, azure and ipc packages and testing

The packages causing build errors are being disabled for now to let us split up
the work in the different driver implementations without blocking integration
into the main branch. The s3 and azure implementations need some effort to add
Stat support. The ipc package needs that work plus some care around hanging
send calls.

storagedriver/ipc/client.go

@@ -1,3 +1,5 @@
+// +build ignore
+
 package ipc
 
 import (