Add extra options to markdown converter

Now, bare URLs are auto-converted, links are opened in a new
window, the ~~strikethrough~~ format also works, and last but not
the least, ChipChoc is now emoji-enabled!

src/App.svelte

@@ -2,7 +2,14 @@
 	import Importabular from "importabular"
 	import showdown from "showdown"
 
-	let converter = new showdown.Converter()
+	let converter = new showdown.Converter({
+		simplifiedAutoLink: true, // automatically convert links...
+		excludeTrailingPunctuationFromURLs: true, // ...but not the trailing punctuation
+		openLinksInNewWindow: true, // don't forget to open in new window!
+		simpleLineBreaks: true, // use two line breaks to start a new paragraph
+		emoji: true, // because why not 😉
+		strikethrough: true, // ~~that also~~
+	})
 
 	let editor