Not with 3.x. The code base is not suited to be run as a shared library, and we should not encourage that.
Besides, the Maven plugin  that generates the meta information is a Maven 2 plugin. It relies on a
Java tool that is ASL licensed. Enrique, thanks for the information. 
HttpComponents - all of them - should make use of that plugin and ship as OSGi bundles.
We'll have to document how to run the code safely as a shared library. In particular,
bundled applications need to shut down connection managers and/or NIO reactors on unload.
Shared resources like SchemeRegistry.DEFAULT must not be modified, and should not be used at all.
I'll try to take care of this later this year. I need to learn Maven anyway.