[modules/pulsectl] add preliminary version of event-based pulseaudio

add a new module based on pulsectl, with pulsein for microphone and
pulseout for speakers.

should eventually become a drop-in replacement for pasink and pasource.

see #917

themes/icons/awesome-fonts.json

@@ -197,6 +197,14 @@
       "prefix": ""
     }
   },
+  "pulseout": {
+    "muted": {
+      "prefix": ""
+    },
+    "unmuted": {
+      "prefix": ""
+    }
+  },
   "amixer": {
     "muted": {
       "prefix": ""
@@ -213,6 +221,14 @@
       "prefix": ""
     }
   },
+  "pulsein": {
+    "muted": {
+      "prefix": ""
+    },
+    "unmuted": {
+      "prefix": ""
+    }
+  },
   "kernel": {
     "prefix": "\uf17c"
   },
@@ -707,4 +723,4 @@
   "thunderbird": {
     "prefix": ""
   }
-}
+}