Add in <main> element, other formatting fixes

Add <main> element and move role of main off <section> and onto it.

Add new lines at end of PHP files to make consistent.

Remove extra white space & indent tags appropriately

Removed an extra "<" from line 313 in functions.php.
add < back in
mini edits

reorder box-sizing rule to be after prefixed declarations.

add new line at end of searchform.php
update modernizr to 2.7.1
remove duplicate declaration of .aligncenter style

already was declared on line 189
remove -webkit-box-sizing
Merge pull request #51 from scottaohara/main_element_and_cleanup

Main element and cleanup