[modules] Add module "date" as alias of "time"

The "time" module now has an alias (symlink) called "date". This is used
to differentiate a widget showing the time from a widget showing the
date.

bumblebee/modules/date.py

@@ -0,0 +1 @@
+time.py

bumblebee/modules/time.py

@@ -3,7 +3,11 @@ import bumblebee.module
 
 class Module(bumblebee.module.Module):
     def __init__(self, args):
-        self._fmt = args[0] if args else "%x %X"
+        module = self.__module__.split(".")[-1]
+
+        default = "%x" if module == "date" else "%X"
+        self._fmt = args[0] if args else default
+
         super(Module, self).__init__(args)
 
     def data(self):