Fix dist target once again

* remove server-related header from cbsasl/src/client.c
* include example/instancepool/pool.h into tarball

Change-Id: Ifa29e138a3d3faef2f202431203b4be1edf8c9ef
Reviewed-on: http://review.couchbase.org/29761
Reviewed-by: Sergey Avseyev <sergey.avseyev@gmail.com>
Tested-by: Sergey Avseyev <sergey.avseyev@gmail.com>