Add 0.20 blog post

source/_topics/templating.markdown

@@ -72,6 +72,7 @@ Home Assistant adds extensions to allow templates to access all of the current s
  - `as_timestamp` will convert datetime object or string to UNIX timestamp
  - `distance()` will measure the distance in meters between home, entity, coordinates.
  - `closest()` will find the closest entity.
+ - `relative_time(timestamp)` will format the date time as relative time vs now (ie 7 seconds)
 
 
 ## {% linkable_title Examples %}