Testing: Add tests for the existing QuestionWidgets.

[heyjamesknight]

This is an intermediate step in preparation for #378, and should be completed before #1423 .

In order to make sure our refactors don't change things they shouldn't, I propose adding tests around Widget construction and updating.

[heyjamesknight]

We want to ensure that the Answer functionality is the same before and after our refactor coming in #1423 and #1422. This includes both the way getAnswer() and clearAnswer() work, as well as internal behavior (such as to a call to deleteMedia in this instance).

The first test was AlignedImageWidget as it is easily generalizable to the other "Binary Name Widgets", including:

• AlignedImageWidget
• AnnotateWidget
• AudioWidget
• DrawWidget
• ImageWebViewWidget
• ImageWidget
• SignatureWidget
• VideoWidget

The other Binary Widget implementations also share major functionality—hopefully we can provide a similarly generalizable test for them:

• BarcodeWidget
• BearingWidget
• ExPrinterWidget
• GeoPointWidget
• GeoShapeWidget
• GeoTraceWidget

The remaining Widgets share a bit less in common, but there should still be opportunities for grouping them and knocking them out together.

[heyjamesknight]

Tests are coming along albeit slowly. The first three BNWs have tests at this point, and I've managed to generalize them so the remaining ones should hopefully go quicker.

[heyjamesknight]

Finished Widgets:

• AlignedImageWidget
• AnnotateWidget
• AudioWidget
• BarcodeWidget
• BearingWidget
• BooleanWidget
• DateTimeWidget
• DateWidget
• DecimalWidget
• DrawWidget
• ExDecimalWidget
• ExIntegerWidget
• ExStringWidget
• GeoPointWidget
• GeoShapeWidget
• GeoTraceWidget
• GridMultiWidget
• GridWidget
• ImageWebViewWidget
• ImageWidget
• IntegerWidget
• ItemsetWidget
• ListMultiWidget
• ListWidget
• OSMWidget
• RangeDecimalWidget
• RangeIntegerWidget
• SelectOneAutoAdvanceWidget
• SelectOneSearchWidget
• SelectOneWidget
• SelectMultiWidget
• SpinnerMultiWidget
• SpinnerWidget
• SignatureWidget
• StringNumberWidget
• StringWidget
• TimeWidget
• TriggerWidget
• UrlWidget
• VideoWidget

These Widgets don't provide answer functionality and will not be tested:

• ExPrinterWidget
• LabelWidget

[heyjamesknight]

Just a few left, planning on wrapping them up tomorrow morning. Sorry for the delay, didn't have as much free time as I was hoping last week!