Document yt-dlp dependency and update docstring

README.md

@@ -37,6 +37,7 @@ using DataFrames
 s |> DataFrame
 ```
 
+Install `yt-dlp`. Optionally install `jq` for pretty-printing and exploring json on the command line.
 
 ## Scripts
 

src/WeatherNews.jl

@@ -108,7 +108,7 @@ function iswnl(title)
 end
 
 """
-Find the current live video's id and update the schedule table if a corresponding row can be found.
+Fetch upcoming live videos' IDs and update the schedule table's corresponding rows.
 
 # Examples
 ```jldoctest