Support ActionSheet width to full-screen-width in 4.7 inch and 5.5 inch devices

- Add 4.7-Retina and 5.5-RetinaHD launch images. Because need get real display sizes
- In iOS 8.0, change `[[UIScreen mainScreen] bounds].size` return value to port/land direction conscious
Is it really needed here? It seems that `return [[UIScreen mainScreen] bounds].size;` w\o any check should works fine. What did you think?