Rounds up the percentile value to multiples of five.
1) Rearranges doughnut chart sectors to match the legend. 2) Fixed  misspelled word.
Included helpers.php file.
Style corrections for the evil-data and used-data pages.
Issue #67: Added 'Traded' column PLACEHOLDER. Does not work yet.
Issue #68: Created a helper function to compute the user's seniority level and percentile.
Merge branch 'develop' of https://github.com/thegooddata/webapp into develop
Rebuilt main.css file.