New wordpress logo icon

Proposal for a Wordpress icon better integrated with others and fixes to align the heart icon on rightbar.
![wordpress-48x48](https://f.cloud.github.com/assets/914785/2199460/f58e61d6-98d4-11e3-82b4-3cfa7333aabd.png)
![rightbar](https://f.cloud.github.com/assets/914785/2199468/000e1eee-98d5-11e3-97b6-8ae446450a88.jpg)