Merge pull request #1 from shenwill/master

Update for keeping the images ratio, date strings in main list, and 4-inch display.
Merge pull request #3 from shenwill/master

An empty detail view with a spinning indicator forever.
major update

1. Update project settings to the lastest XCode and SDK.
2. Due an rotation issue on iOS 6, deployment target set to 4.0
3. Disable sharing except email sharing
4. Improve article layout by using CSS 3