feat(platform): add support for `Arch`

* Semi-automated using https://github.com/myii/ssf-formula/pull/40

.cirrus.yml

       # - INSTANCE: default-fedora-30-develop-py3
       # - INSTANCE: default-opensuse-leap-15-develop-py3
       # - INSTANCE: default-amazonlinux-2-develop-py2
+      # - INSTANCE: default-arch-base-latest-develop-py2
       # - INSTANCE: default-debian-9-2019-2-py3
       - INSTANCE: default-ubuntu-1804-2019-2-py3
       # - INSTANCE: default-centos-7-2019-2-py3
       # - INSTANCE: default-fedora-30-2019-2-py3
       # - INSTANCE: default-opensuse-leap-15-2019-2-py3
       - INSTANCE: default-amazonlinux-2-2019-2-py2
+      - INSTANCE: default-arch-base-latest-2019-2-py2
       # - INSTANCE: default-debian-9-2018-3-py2
       # - INSTANCE: default-ubuntu-1604-2018-3-py2
       # - INSTANCE: default-centos-7-2018-3-py2
       - INSTANCE: default-fedora-29-2018-3-py2
       - INSTANCE: default-opensuse-leap-15-2018-3-py2
       # - INSTANCE: default-amazonlinux-2-2018-3-py2
+      # - INSTANCE: default-arch-base-latest-2018-3-py2
       # - INSTANCE: default-debian-8-2017-7-py2
       # - INSTANCE: default-ubuntu-1604-2017-7-py2
       - INSTANCE: default-centos-6-2017-7-py2
       # - INSTANCE: default-fedora-29-2017-7-py2
       # - INSTANCE: default-opensuse-leap-15-2017-7-py2
       # - INSTANCE: default-amazonlinux-2-2017-7-py2
+      # - INSTANCE: default-arch-base-latest-2017-7-py2
   bundle_install_script: bundle install
   verify_script:
     - bin/kitchen verify ${INSTANCE}

kitchen.yml

       provision_command:
         - curl -o bootstrap-salt.sh -L https://bootstrap.saltstack.com
         - sh bootstrap-salt.sh -XdPbfrq -x python2 git develop
+  - name: arch-base-latest-develop-py2
+    driver:
+      image: netmanagers/salt-develop-py2:arch-base-latest
+      provision_command:
+        - curl -o bootstrap-salt.sh -L https://bootstrap.saltstack.com
+        - sh bootstrap-salt.sh -XdPbfrq -x python2 git develop
+      run_command: /usr/lib/systemd/systemd
 
   ## SALT `2019.2`
   - name: debian-9-2019-2-py3
   - name: amazonlinux-2-2019-2-py2
     driver:
       image: netmanagers/salt-2019.2-py2:amazonlinux-2
+  - name: arch-base-latest-2019-2-py2
+    driver:
+      image: netmanagers/salt-2019.2-py2:arch-base-latest
+      run_command: /usr/lib/systemd/systemd
 
   ## SALT `2018.3`
   - name: debian-9-2018-3-py2
   - name: amazonlinux-2-2018-3-py2
     driver:
       image: netmanagers/salt-2018.3-py2:amazonlinux-2
+  - name: arch-base-latest-2018-3-py2
+    driver:
+      image: netmanagers/salt-2018.3-py2:arch-base-latest
+      run_command: /usr/lib/systemd/systemd
 
   ## SALT `2017.7`
   - name: debian-8-2017-7-py2
   - name: amazonlinux-2-2017-7-py2
     driver:
       image: netmanagers/salt-2017.7-py2:amazonlinux-2
+  - name: arch-base-latest-2017-7-py2
+    driver:
+      image: netmanagers/salt-2017.7-py2:arch-base-latest
+      run_command: /usr/lib/systemd/systemd
 
 provisioner:
   name: salt_solo

syslog_ng/osfamilymap.yaml

 ---
 Gentoo:
   package: app-admin/syslog-ng
+
+Arch:
+  service: syslog-ng@default.service

test/integration/default/controls/service_spec.rb

+syslogng_service =
+  case platform[:name]
+  when 'arch'
+    'syslog-ng@default.service'
+  else
+    'syslog-ng'
+  end
 control 'SyslogNG service' do
   title 'should be running and enabled'
 
-  describe service('syslog-ng') do
+  describe service(syslogng_service) do
     it { should be_enabled }
     it { should be_running }
   end

test/integration/default/inspec.yml

   - platform-name: suse
   - platform-name: freebsd
   - platform-name: amazon
+  - platform-name: arch