Add cross-report filtering and interactivity

[nielsdejong]

Addition: a feature to let dashboard builders specify charts that are connected, e.g. filtering a report by clicking/selecting parts of the another visualization:

• Click on a table cell
• Click on Nodes/relationships in a graph
• Click on a bars in a bar chart

This click action should set a parameter $neodash_xyz, just like a parameter selection. The parameter can then be used in other reports.