MRC, DIR: updated BabuDB to 0.3.0 (includes support for disk indices larger...

MRC, DIR: updated BabuDB to 0.3.0 (includes support for disk indices larger than 2GB, automatic conversion of former database formats on startup, as well as various other small enhancements and bug fixes)

git-svn-id: https://xtreemfs.googlecode.com/svn/trunk@1407 f8528748-c2c0-11dd-ba5c-d3b7c2b3b534