Fixed #932 -- Highlighted currently selected search filters in bold.

Highlighted filters have css style font-weight: bolder. Because "bolder" is slightly more apparent than "bold".

https://openhatch.org/bugs/issue932

![932_highlight_terms_bold](https://f.cloud.github.com/assets/954858/2118517/d0a2fbb2-910d-11e3-9806-dce69eb64b59.png)