Implement quotas and limits

GH-6.
Update Changelog
Rearrange upgrade documentation
Move Install docs to doc/.
Move fix_scores to doc.
Remove development submodule and update README about it.
Fix .git* files
Fix install.php to create database if it is missing.
jQuery update to 1.11.0 and jQuery-UI 1.10.4
Fix JSON output for newer jQuery on scoring
Update CHANGELOG
Fix event signup start and end datepicker with datetimepicker
Update CHANGELOG.md
Hide preliminary groups until published
Update CHANGELOG
Fix issue number links
Add events that are registering or soon registering to the frontpage
Update CHANGELOG.md
Make version 2014.02.21