Install Ansible via pip instead of Homebrew

When installed via Homebrew, it seemed not possible to make molecule
work correctly. So instead we install both ansible and molecule via pip,
and everything works.

zsh/python.zsh

@@ -0,0 +1,25 @@
+#
+# Python environment setup
+#
+
+install_python_global_packages () {
+  local packages=(
+    'ansible'
+    'molecule[docker]'
+  )
+
+  if (( $+commands[brew] )); then
+    brew list python >/dev/null || brew install python
+  fi
+
+  local pipcmd="pip"
+  if (( $+commands[pip3] )); then; pipcmd="pip3"; fi
+
+  $pipcmd install --upgrade setuptools
+  $pipcmd install --upgrade "${packages[@]}"
+}
+
+# Aliases
+alias ap="ansible-playbook"
+alias av="ansible-vault"
+alias mo="molecule"