Added an extra if loop to retrieve description values from sites like the New York Times who have malformed it by using value instead of content. See http://www.nytimes.com/2012/06/13/world/middleeast/violence-in-syria-continues-as-protesters-killed.html for an example of this bad code.
Now can add title and description from head meta even if no Open Graph tags exist.
Merge pull request #6 from AramZS/master

Added to retrieve using value attribute, fallback.