Added views and controller for the StatEntry model
Merge branch 'master' into create_stats
added permission check to StatEntry model
created relation between user and stat_entry model (stat entry belongs to a user, user has many stat entries)
fixed permission issues for deleting stat entries
added possibility to filter the stat entries
merged master branch into create_stats
Merge branch 'master' into create_stats
merged with master branch and updated some views
added highcharts module and integrated a pie chart to the view
fixed indention (replace tabs by spaces)
merged create_stats branch into master