Updates for 0.90 and Lucene 4?

[konklone]

This is a horribly general issue to open, I know, but I don't really know how to process Elasticsearch's ultra-specific release notes. There's a giant wave of new features and breaking changes in 0.90, spread across 4 releases, and I wonder if rubberband needs any updates to be compatible with them:

0.90 Stable
0.90 RC2
0.90 RC1
0.90 Beta