some minor fixes for endpoint and namespace

 endpoint.c: fix name comparison for endpoint
namespace.c: don't try to find when name is NULL

Signed-off-by: Przemyslaw Kedzierski <p.kedzierski@samsung.com>
namespace: hold mutex while creating a new instance
preserve payload record padding when \0-bytes records are used

Based on a patch from: Daniel Kowalski <d.kowalski@samsung.com>
Merge branch 'master' of https://code.google.com/p/d-bus