Give precedence to feature style
Distinct style function types
Add option to process GPX extensions nodes

Fixes #1791.
Add tests for GPX extensions
Automatically dispose the ViewportSizeMonitor
Dispose the tiles removed from the cache
Update to use the correct default style function namespace
Test to make sure that feature styles take prececence
Move defaults style into `style.js`
Merge pull request #2394 from tonio/style_order

Give precedence to feature styles
Write version in builds
Merge pull request #2442 from tsauerwein/build-version

Write library version in build files
Merge pull request #2420 from gingerik/gpx-extensions

PR for GPX: read extensions tags
Unconditionally add version info to the build header

This reworks the changes in #2442 so we always include the version info, regardless of whether the module is run as main or not.  This also addresses a few lint related issues.
Merge pull request #2446 from tschaub/version

Unconditionally add version info to the build header.
Fix WKT writers output type
Improve wording of ol.Map description
Merge pull request #2449 from probins/patch-1

Improve wording of ol.Map description
Fix typo in ol.Map test.
Merge pull request #2452 from marcjansen/test-typo

Fix typo in ol.Map test.