added datetime widget

.config/eww/widgets/datetime.scss

@@ -0,0 +1,4 @@
+.datetime {
+  background: #2E3440;
+  color: #E5E6E7;
+}

.config/eww/widgets/datetime.yuck

@@ -0,0 +1,17 @@
+(defwidget datetime []
+  (box :class "datetime"
+       :halign "center"
+       :valign "center"
+    { time == ''
+      ? ''
+      : time
+    }
+  )
+)
+
+(defvar time-visible false)
+(defpoll time :interval "1s"
+              :initial "initial-value"  ; optional, defaults to poll at startup
+              :run-while time-visible   ; optional, defaults to 'true'
+  `date +"%H:%M - %a, %d %b"`        ; https://www.man7.org/linux/man-pages/man1/date.1.html
+)