Update of VPP_STABLE_VER files

- use new vpp ref build - ubuntu 16.04:
  18.01-rc0~358-g60d48bb~b3298_amd64

- use new vpp ref build - centos7:
  18.01-rc0~358_g60d48bb~b3295.x86_64

- builds tested by semiweekly jobs:
  https://jenkins.fd.io/view/csit/job/csit-vpp-verify-master-ubuntu1604-semiweekly/94/
  https://jenkins.fd.io/view/csit/job/csit-vpp-verify-master-centos7-semiweekly/94/

Change-Id: Ie2220976f536b02832834effb17c4e5d35abe2be
Signed-off-by: Jan Gelety <jgelety@cisco.com>