Alpine Linux: add basic support

salt/map.jinja

@@ -91,6 +91,16 @@ that differ from whats in defaults.yaml
       'salt_api': 'salt',
       'salt_ssh':  'salt',
     },
+    'Alpine': {
+      'salt_master': 'salt-master',
+      'salt_minion': 'salt-minion',
+      'salt_syndic': 'salt-syndic',
+      'salt_cloud': 'salt-cloud',
+      'salt_api': 'salt-api',
+      'salt_ssh': 'salt-ssh',
+      'pygit2': 'py2-pygit2',
+      'libgit2': 'libgit2',
+    },
     'FreeBSD': {
       'salt_master': 'py27-salt',
       'salt_minion': 'py27-salt',