Check for Ign/Hit membership instead of == in aptpkg.refresh_db

[rallytime]

What does this PR do?

Ubuntu 16 lists the first "column" of data differently than previous versions of Ubuntu. Instead of check for Hit or Ign explicitly with ==, we should use in instead to make sure display the Hit and Ign returns.

Ubuntu 16 looks like this:

Hit:1 http://repo.saltstack.com/apt/ubuntu/16.04/amd64/latest xenial InRelease
Hit:2 http://archive.ubuntu.com/ubuntu xenial InRelease
Get:3 http://archive.ubuntu.com/ubuntu xenial-updates InRelease [95.7 kB]
Get:4 http://archive.ubuntu.com/ubuntu xenial-security InRelease [94.5 kB]

Ubuntu 14 looks like this:

Hit http://repo.saltstack.com trusty InRelease
Ign http://archive.ubuntu.com trusty InRelease
Get:1 http://archive.ubuntu.com trusty-updates InRelease [65.9 kB]
Get:2 http://archive.ubuntu.com trusty-security InRelease [65.9 kB]

What issues does this PR fix or reference?

This should clear up the integration.modules.pkg.PkgModuleTest.test_refresh_db test failures on Ubuntu 16, as it should now be unlikely that a {} will be returned if no Gets are in the apt-get -q update return:

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/salttesting/helpers.py", line 547, in wrapper
    return func(cls)
  File "/usr/local/lib/python2.7/dist-packages/salttesting/helpers.py", line 68, in wrap
    return caller(cls)
  File "/testing/tests/integration/modules/pkg.py", line 198, in test_refresh_db
    self.assertNotEqual(ret, {})
AssertionError: {} == {}

Tests written?

Yes - there is already a test written for this which found this change in behavior.

Please review Salt's Contributing Guide for best practices.