Fix suggestion for non-latin blog title

Hi.
Thanks for the great theme.
I just want to let you know that if the blog has non-latin title ex greek then the substr you use in header.php to get the title’s first letter isn’t work correct.
So the suggested fix is the following.
Replace the
echo '<span class="first-letter">' .substr( get_bloginfo('name'), 0, 1 ) . '</span>';
in line 34 in header.php with the following:
echo '<span class="first-letter">' . mb_substr( get_bloginfo('name'), 0, 1 ) . '</span>';

Bests
Lena