[DATALAD RUNCMD] run codespell throughout fixing typos automagically

=== Do not change lines below ===
{
 "chain": [],
 "cmd": "codespell -w",
 "exit": 0,
 "extra_inputs": [],
 "inputs": [],
 "outputs": [],
 "pwd": "."
}
^^^ Do not change lines above ^^^

js/reveal.js

@@ -1252,7 +1252,7 @@ export default function( revealElement, options ) {
 
 	/**
 	 * Returns true if we're currently on the last slide in
-	 * the presenation. If the last slide is a stack, we only
+	 * the presentation. If the last slide is a stack, we only
 	 * consider this the last slide if it's at the end of the
 	 * stack.
 	 */