Style touches

## Need
The application looks really ugly and that's a reason why we didn't ship it earlier.

## Project Issues

#### Projects page
- [ ] ~~Add a draft for the Projects page (this should be easy to read for anyone looking at the page from stalkers to companies wanting to know more about us)~~
- [x] Show logo and description

#### Profile page
- [x] Empty profiles look ugly. Activity and Affiliation must not appear without any Activity or Affiliation

#### Edit profile page
This should be the first page a new user sees
- [x] Space out the forms
- [x] Instead of an add new link, add a plus icon at the right of the heading and a caption with what the button does (e.g. Links +, WoUSO +)

#### Form errors
- [x] CSS class that styles the errors from the django forms

#### All pages
- [x] Remove back to (people)|(projects)|(anything) from the bottom of the pages
- [x] Remove irrelevant links from base template