Fix the Mobile networks icon in Settings

-shrinked a little
-centered

See the screenshots:  https://drive.google.com/folderview?id=0BxY75MbFAKsXMzF3YXJZdUhVNm8&usp=sharing

Change-Id: Ia77dbf4417a3c4dd09adc11990406e97b482ae46
Merge "Fix the Mobile networks icon in Settings" into kitkat