Mostly general

Mostly general fixes:

* Loading Javascript files locally (was unacceptable lag loading the
WebView)
* Imports CSV better (uses the CSV module!)
* Bugs in dialogs sorted out
* Uses unit-tested descriptives module
* Clipboard operations for the grid are much better
* Outputs descriptives with multiple results (e.g., quartiles, mode,
proportions, frequencies) better
* Building new grid object that resizes properly