Browse page redesigned

- Browsing page is now simpler.
- Added 4 different filtering tools to the browsing page:
    - Category -filter, which filters issues by the selected category.
    - Sort- filter, which lets you organize the filtered issues in either hot, new or top order.
    - Searching ("hunting") -tool, pretty self-explanatory.
    - Tag -filter, which lets you filter issues by tags.
    - All these tools can work together.
- Browsing page issues now show more data.
- Browsing page optimized, loads faster.
- Again, multiple bug fixes have been commited, like the overflowing activity box on /user