This updates ESLint and our shared eslint-config-openlayers to use Prettier. Most formatting changes were automatically applied with this:
npm run lint -- --fix
A few manual changes were required:
* In `examples/offscreen-canvas.js`, the `//eslint-disable-line` comment needed to be moved to the appropriate line to disable the error about the `'worker-loader!./offscreen-canvas.worker.js'` import.
* In `examples/webpack/exapmle-builder.js`, spaces could not be added after a couple `function`s for some reason. While editing this, I reworked `ExampleBuilder` to be a class.
* In `src/ol/format/WMSGetFeatureInfo.js`, the `// @ts-ignore` comment needed to be moved down one line so it applied to the `parsersNS` argument.
The renderer now accesses the zDirection member directly if it exists.
This also has the advantage of not advertising any object methods that
hav no use for most tile sources.
Via zDirection, the renderer's selection of a tile source's resolution can be
controlled if the view's resolution does not match any tile source resolution.
Currently the zDirection option is only available for Zoomify. The comment
https://github.com/openlayers/openlayers/issues/9343#issuecomment-474341033
describes why caution is advised when using zDirection for other sources.
ol/source/Tile~TileSource#getZDirection has been added to avoid having the
getZDirection method solely in the Zoomify source - just to document the
possibility.
Remove 'extent' because the parent Source class does not contain
'extent' on its options or use options.extent in the constructor.
Also removed 'extent' from 'Options' for 'TileSource'.
If `VOID` is used, TypeScript is not able to figure out what the function parameters are.
Before:
```
$ npx tsc | wc -l
1188
```
After:
```
$ npx tsc | wc -l
1169
```
TileWMS objects take a gutter option but do not have a public getter
for it. This makes it convoluted for user code to recreate the object
(ex: in the case of serialization/deserialization).
- the getGutterInternal() method is renamed to getGutter;
- the getGutter(projection) method is renamed to getGutterForProjection,
which is also more explicit.
The getGutter method was not API and is only used by the renderer.
