Many structural improvements and bugfixes to flot and highcharts

Release notes:

Fixes: 
- Rendering of the correct labels under the correct ticks when rendering multiple series   (series were previously mixed)
- Fix for showing a serie with an empty associated xlabel (graphs used to freeze, now it will show '(undefined)')
 
- CSS fix preventing x-axis labels from rendering outside the graph area
- Fix for rendering x-axis values, in case the first serie has gaps or no data at all. Now if the first serie has gaps or no data, all x-axis values will still be shown
 
- Fixed the built in filter options
- Improved the CSS for the built-in filter
- Series constraint wasn't applied on the filter entities
- Improved data constraint when using filters
 
- Fixed microflow on click action, wasn’t working previously
 
- Fix for not rendering the chart in case of empty x-axis labels
- Improved Date positioning on x-axis, in case of missing values or small ranges (e.g. one or two values)
- Implemented timezone support, based on localized yes/no the dates will be translated before rendering
- Added support for empty dates, instead of rendering separate points for each empty date it will now be plotted in a single '(undefined)' column
- Fix for showing week nr's according to the ISO standard. Removed some redundant localization functions
 
- Fixed the highchart implementation, still unstable but has a much better chance of rendering now

- Fixed sort order when using multiple series (previously sorted on first serie only)
- Implemented sort order on enumeration name   (previously sorted on first serie enum name only)

- Fixed usage of the Pie chart using associations, or enumerations as categories
 

Feature
- Added the 'stacked bar' option
- New Line Graph option to hide the circels around all datapoints in a line graph
- New option to group dates by week
- Added a new CSS class .VerticalLabels which renders X-Axis labels in a 45 degree angel