Get random topic from the database
Start to wire up the hack page with real data from db
Load languages from db
Query solutions count from db
Get solution list from db
Some frontend logic actually
Implemented language and solution switching
Save hack #4

One user could only submit one hack for the same topic and
language.
Only logged-in users can submit hacks
Merge pull request #4 from web-hackers/4-backend-logic

backend logic