Fixes geerlingguy#49: Remove git-svn from defaults.

Bump minimum Ansible version to 2.5 with new filter.

Fixes geerlingguy#44: Fix deprecation warnings for git_install_from_s…

…ource.

Fixes geerlingguy#39 *correctly*: Fix deprecation warning in Ansible …

…2.7.

Fix broken behavior under Ansible 2.7 due to yum module change.

Fix deprecation warnings in Ansible 2.5 for state 'present'.

Issue geerlingguy#35: Fix source build for Ubuntu 18.05 'Bionic'.

Fixes geerlingguy#34: Bump minimum Ansible version to 2.4 and update …

…use of include.

Fixes geerlingguy#33: Fix source build install failure on Ubuntu 16.04.

PR geerlingguy#25 follow-up: Just a few stylistic tweaks.