adjust include statements (v2)

Use "#include <somefile.h>" style for external or exported headers only.

changes since v1:
 - adjusted formatting as Stéphane suggested

Signed-off-by: S.Çağlar Onur <caglar@10ur.org>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Use pthread_atfork() to unlock mutexes after fork()

Signed-off-by: Andrey Mazo <mazo@telum.ru>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>