dhcpcd: Install and configure dhcpcd

`dhcpcd` is a fully-featured network manager, without all the bloat of
`NetworkManager`.

roles/dhcpcd/tasks/main.yml

@@ -0,0 +1,21 @@
+- name: ensure dhcpcd is installed
+  package:
+    name=dhcpcd
+    state=present
+
+- name: ensure dhcpcd is configured
+  template:
+    src=dhcpcd.conf.j2
+    dest=/etc/dhcpcd.conf
+    mode=0644
+  notify: restart dhcpcd
+
+- name: ensure dhcpcd starts at boot
+  service:
+    name=dhcpcd
+    enabled=yes
+- meta: flush_handlers
+- name: ensure dhcpcd is running
+  service:
+    name=dhcpcd
+    state=started