Update example

Author: kgryte

lib/node_modules/@stdlib/repl/presentation/examples/presentation.txt

@@ -24,21 +24,51 @@
 ---
 
 | \_\*Standard Library\s\s
-\s
 
---
 
-• utilities
-  • \rgroupBy\s
-  • \rpluck\s
+---
 
---
+| \_utilities\s
 
-• data structures
-  • \rStack\s
-  • \rFIFO\s
+• \rgroupBy\s
 
---
+```
+function indicator( v ) {
+    if ( v[ 0 ] === 'b' ) {
+        return 'b';
+    }
+    return 'other';
+};
+var collection = [ 'beep', 'boop', 'foo', 'bar' ];
+var out = groupBy( collection, indicator )
+```
+
+
+---
+
+• \rpluck\s
+
+```
+var arr = [
+    { 'a': 1, 'b': 2 },
+    { 'a': 0.5, 'b': 3 }
+];
+var out = pluck( arr, 'a' )
+```
+
+
+---
+
+| \_Data Structures\_
+
+• \rLinkedList\s
+• \rDoublyLinkedList\s
+• \rStack\s
+• \rFIFO\s
+• ...
+
+
+---
 
 • consistent interfaces