Fix errors in HTML

[jamescooke]

There are some errors in HTML when a site is run through validator

http://validator.w3.org/check?uri=jamescooke.info&charset=(detect+automatically)&doctype=Inline&group=0

Appear to be around charset and encoding.

[jamescooke]

Worth checking out this: https://github.com/svenkreiss/pelican-theme-validator