User profile page and post page templates: add extra wrappers

Add extra wrapper into primary details section to allow laying textual items out on the right of the avatar.

When implementing Sitepoint's custom theme, this was one of the places where we needed to add extra markup to be able to achieve a 2-column design in the primary user details block (see screenshot).

![userprofileextrawrapper](https://cloud.githubusercontent.com/assets/5316880/2814500/ce440304-ceaa-11e3-8911-f06b55dadf90.png)

Another place where we had a similar situation seems to have been already updated in af69b78ecbb79b881f8f577ad61d69875ae9fa99