Add get_selections() and set_selections() for dpkg.

This module will enable to freeze a package at a certain version, with the "hold" state.
Add TODO, amend later... FIXME.
possible fix for https://github.com/saltstack/salt/issues/5567
possible fix for https://github.com/saltstack/salt/issues/5567
Added initial stubbed hg fileserver.
Implemented some functions for hgfs
Because of the recent salt sys module rename, force absolute imports.
Revert "Because of the recent salt sys module rename, force absolute imports."

This reverts commit 81e435f272baa2f826e55f5d84a97185c55661c8.
Revert "Renamed `sysmod` module to `sys` while enforcing absolute imports."

This reverts commit 174a3e5b6ca25bde8d8b5b1db73fe038c92c4474.
Revert "Fixed documentation linking."

This reverts commit 758e789d12867794a653d5da3d216354b97d6d18.
Revert "Renamed `localemod` module to `locale` while enforcing absolute imports."

This reverts commit 791dc53ca6b45ba6b90789a3f196b8e57a4d889c.
Revert "Renamed `ldapmod` module to `ldap` while enforcing absolute imports."

This reverts commit c4c58370d22972cfc3ca82da1c7fa1cd91fd69a0.
Revert "Renamed `gentoolkitmod` module `gentoolkit` while enforcing absolute imports."

This reverts commit 0f08e6088b9cfc9c201eb042caafbe6817cdf469.
Revert "Renamed `djangomod` module and state to `django` while enforcing absolute imports."

This reverts commit 2f4d82b295cf1354c0941146af3d5d08e288cc8f.
Revert "Renamed `debconfmod` module and state to `debconf` while enforcing absolute imports."

This reverts commit 04e3874b424971ec0bf4944ed60d4f9f4263b132.
Revert "Since the module/state got renamed, let's leave a link pointing to the new names."

This reverts commit e724e541994ea9250dafed94fc18e1f955777db1.
Revert "Since there are some links to `salt.modules.cmdmod` point the user to the correct module."

This reverts commit 1599cd0ba5974040aa96b1dd7655fcd65b688bec.
Revert "`salt.modules.cmdmod` renamed to `salt.modules.cmd` while enforcing absolute imports."

This reverts commit 3fa341280bbb32be3f2956c842d459c80015890e.
Revert "By enforcing absolute imports, there's no need for module name aliases."

This reverts commit a1a2b49a723c2f66cb91cd46727525b18808a34d.
Add documentation to style guide as to why absolute imports should be avoided.