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This release:
- allows dynamically updating an already constructed marker and
symbol layer. This makes it easier to use that layer in
widget applications (PR 285, 286).
- adds support for marker layers with no markers (PR 288)
- updates the Google JS API version form 3.31 to 3.34 (PR 289)
- updates the build process to use webpack 4 (PR 290)
- adds the return type of the marker, symbol and geojson layer
to the factory functions (PR 291)
- autoformats the JS parts of the code with prettier (PR 279)
- adds checks on the integrity of the documentation as part
of the build process (PR 293).