Util: Improve code to get connection credentials Adds support to get SELINUX context and make code more abstract so that struct ucred (if availale) can be used w/o redefining uid,gid,pid to int32. Also gives a layer of indirection that may come handy if we want to improve the code further in the future. Signed-off-by: Lukas Slebodnik <lslebodn@redhat.com> Reviewed-by: Michal Židek <mzidek@redhat.com>