Release 3.0.0-rc2

[cowtowncoder]

Jackson 3.0.0-rc2 is being released:

FasterXML/jackson-future-ideas#81

all other components have been successfully released and all except for Jakarta-RS providers are accessible via Maven Central. Providers should get there within 10-15 minutes.

[pjfanning]

Done.

I haven't had much luck with Sonatype support. Publishing with the CI fails due to HTTP failures. I had to manually publish jars using Bundle Uploads in the Nexus UI.