Allow package to be published in npm registry

I've contacted the maintainer of the https://www.npmjs.org/package/openlayers package to see if we can take over ownership.  Until then, we can publish packages under the name 'ol'.
Handle activation/deactivation in draw interaction
Add tests for ol.interaction.Draw#setActive
Add tests for ol.interaction.Draw#setMap
More restrictive type for ol.style.Circle#getImage
More restrictive type for ol.style.Icon#getImage
Mark ol.style.Image with @api

This is to be able to do `imageStyle instanceof ol.style.Image` in applications.
Mark ol.style.Image#getImage with @api
Merge pull request #2773 from elemoine/getimage

Type-related changes to ol.style.Image
Remove unused distinctFeatures object in ol.interaction.Modify#handlePointerDown

The object is filled but never used.
Merge pull request #2771 from tschaub/pre-releases

Allow package to be published in npm registry.
Merge pull request #2774 from fredj/dead-code

Remove unused distinctFeatures object in ol.interaction.Modify#handlePointerDown
Remove 'examples/bootstrap' path from example filter

The directory was moved to resources/bootstrap in 6c5377eebef
Move jquery.min.js to resources
Update jquery to 1.9.1
Fix ol externs definitions

* Namespaces must be defined;
* Interfaces must be initialized.
Fix namespacing convention
Hide the rotate control when the rotation is 0

To prevent the cursor to be displayed as a pointer (only happens with bootstrap)
Add 'tooltip'-tag to KML example.

Fixes #2708.
Merge pull request #2782 from fredj/hide-rotate

Hide the rotate control when the rotation is 0