[docker] Cleanup, minor fixes, formula bump

[docker] Cleanup, minor fixes, formula bump

* ship prebuilt salt master conf for better readability:
  - enable x509.sign_remote_certificate (for prx VCP nodes);
* refactor Salt master CA handling:
  - preinstall `salt_minion_dependency_packages` and
   `salt_minion_reclass_dependencies` inside docker image;
  - persistent /etc/pki;
  - run salt.minion on cfg01 to generate master keys;
* bump container formulas to 1 Sep 2018 versions or newer:
  - inject date into Docker makefile, forcing a fresh fetch of all
    salt formulas from upstream git repos;
* workaround broken salt-formula-designate's meta/sphinx.yml:
  - the DEB package version of salt-formula-designate uses `cmd.shell`
    to query dpkg on the minion, while the git repo version still
    uses `cmd.run`, running into parsing issues;
  - temporarily disable sphinx metadata generation for designate until
    upstream git repo syncs with the DEB version;
* upstream: salt-formula-salt AArch64 salt.control.virt support:
  - retire salt-formula-salt git submodule and related patches;
* skip installing reclass distro package (already installed via pip
  inside the container);
* limit initial pillar_refresh call to nodes on jumphost;
* remove unused salt-formula-nova git submodule;

JIRA: FUEL-383

Change-Id: I883b825e556f887a5e31f8a43676dcd8ece6dfde
Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>