base: deletion of redundant/obsolete meta and rev.

• Removes meta content-type. http://code.google.com/p/doctype-mirror/wiki/MetaCharsetAttribute

• Removes obsolete meta element to specify document-wide language.

• Replaces deprecated link rev in favour of link rel. http://www.whatwg.org/specs/web-apps/current-work/multipage/obsolete.html#attr-link-rev