Move roots_entry_meta into its own template

No need for this HTML to be in a function. Now instead of calling the
function, just use get_template_part

templates/content.php

@@ -10,7 +10,7 @@
   <article id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
     <header>
       <h2><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></h2>
-      <?php roots_entry_meta(); ?>
+      <?php get_template_part('templates/entry-meta'); ?>
     </header>
     <div class="entry-content">
       <?php the_excerpt(); ?>