shower/shower — pull request #100 by fhemberger (2012-12-29 13:29:15+00:00)
Title: Create valid ID values for slides

Valid tokens for ID attributes must begin with a letter ([A-Za-z]) and may be followed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods ("."). This is necessary to access those IDs by `document.getElementById()` or `document.querySelector()`.