Added an animated gif as indeterminate progress indicator
Added jQuery Cookie plugin for cookie management
MeasurementController defines a filter for cookie management
Replacing all occurences of $this->log with Cakelog::write. First one seems no longer to work
Exporting data is no longer done via ajax as this won't trigger the file download dialog. Therefor some changes were necessary in the MeasurementController and in export.js. 
Getting data for charts is also using ClimateElement objects and corresponding factory.
Added a method to MeasurementController that can be used to get memory consumption of php variables.
Getter for elemenID in ClimateElement class.
Changing virtualFields name for all ClimateElements to something that is more logical.
Retreiving export data from the server uses a cookie and a special token in order to be able to show a working indicator to the user. 
Reducing font size for navigation bar und tabs so it matches the unversities layout. 
All Checkboxes for selecting climate elements (exporting) have a minimum width now. Looks much better this way.