Rework handling of skipped features in replay
Add getSource getter in ol.source.ImageVector
Measure example: correct source link
Merge pull request #1996 from probins/measure

Measure example: correct source link
Make handling of skipped features faster
Merge pull request #1997 from elemoine/skipped-features-performance

Make handling of skipped features faster
Merge pull request #1994 from oterral/add_export

Add getSource function in ol.source.ImageVector
Merge pull request #1990 from elemoine/select-bug

Rework handling of skipped features in replay
Adding a JSDoc configuration for generating metadata on exported symbols

This generates info for all symbols annotated with "@todo api" (when Plovr is replaced, this will become "@api").  Generated metadata is written to stdout.  A separate process will handle the output.
Add a task to generate metadata on exported symbols

This runs JSDoc with the "symbols" config, providing a list of source files that have been changed since the previous run.  The output is used to generate metadata files containing exported symbol info for each of the source files.  A separate task will be run to generate the exports.js file.  These same metadata files will be used by a build tool.
Write a single symbols file
Add extends info to symbol metadata
Rename group to package
Annotations for exports
Removing old *.exports for completeness
Write out sorted symbols, excluding inherited ones on private classes

There are cases where a private class may inherit an exportable member (e.g. ol.DebugTile_#getTileCoord comes from ol.Tile#getTileCoord).  We want to avoid making these exportable.
Allow main method to be called from elsewhere
Task for generating a limited set of exports
Use new generate-exports.js task
Regenerate symbols if parents have changed

The generate-symbols.js task runs JSDoc on source files.  Because this takes a long time (13s) to run on the whole library, the resulting symbols file includes additional metadata to make it possible to do incremental symbol generation on subsequent runs.  The 'path' and 'extends' metadata for a symbol are used to determine what needs to be regenerated.