Reverted some changes from the last commits (see below)

In the pulseaudio widget:
- Renamed 'factory' to 'worker', to match other widgets.
- Removed lengthy sed explanation.
- Removed tooltip.
- Removed default settings.

widgets/pulseaudio.lua

@@ -11,40 +11,22 @@ local awful        = require("awful")
 local wibox        = require("wibox")
 local string       = { gmatch = string.gmatch,
                        match  = string.match }
+local setmetatable = setmetatable
 
 -- PulseAudio volume
 -- lain.widgets.pulseaudio
 
-local function factory(args)
+local function worker(args)
     local pulseaudio = {}
     
     local args        = args or {}
     local devicetype  = args.devicetype or "sink"
     local timeout     = args.timeout or 5
+    local settings    = args.settings or function() end
     local scallback   = args.scallback
-    
     local cmd         = args.cmd or ("pacmd list-" .. devicetype .. "s | sed -n -e '/* index:/,/index:/ !d' -e '/* index:/ p' -e '/base volume:/ d' -e '/volume:/ p' -e '/muted:/ p' -e '/device\\.string/ p'")
-    -- sed script explanation:
-    --  '/* index:/,/index:/ !d' removes all lines outside of the range between the line containing '* index:' and the next line containing 'index:'. '* index:' denotes the beginning of the default device section.
-    --  '/* index:/ p' prints the line containing '* index:'.
-    --  '/base volume:/ d' removes the line containing 'base volume:'. This is necessary due to the following script.
-    --  '/volume:/ p' prints the line containing 'volume:'.
-    --  '/muted:/ p' prints the line containing 'muted:'.
-    --  '/device\\.string/ p' prints the line containing 'device.string:'.
-    
-    local settings    = args.settings or function()
-            widgettext  = volume_now.left .. "%"
-            tooltiptext = volume_now.left .. "% (" .. devicetype .. " " .. volume_now.index .. " \"" .. volume_now.device .. "\")"
-            if volume_now.muted == "yes" then
-                widgettext  = "Mute"
-                tooltiptext = "Mute/" .. tooltiptext
-            end
-            widget:set_text(widgettext)
-            tooltip:set_text(tooltiptext)
-        end
     
     pulseaudio.widget = wibox.widget.textbox()
-    pulseaudio.tooltip = awful.tooltip({ objects = { pulseaudio.widget } })
     
     function pulseaudio.update()
         if scallback then cmd = scallback() end
@@ -68,7 +50,6 @@ local function factory(args)
             volume_now.right = volume_now.channel[2] or "N/A"
 
             widget = pulseaudio.widget
-            tooltip = pulseaudio.tooltip
             
             settings()
         end)
@@ -79,4 +60,4 @@ local function factory(args)
     return pulseaudio
 end
 
-return factory
+return setmetatable({}, { __call = function(_, ...) return worker(...) end })