Provide support for automating maintenance tasks

[Lambeaux]

Scope

Applies to experiment: https://github.com/connexta/osg-eyes/tree/mvn-indexing

Goal

Add basic Quartz (or whatever) support for automatically handling tasks such as rebuilding the index.

Notes

If push comes to shove, this thing becomes popular, and remains useful over a long period of time, I'm just thinking that a simple nightly reindexing job could be good enough to punt on incremental updates (#17) since for mirror instances the index is relatively tiny compared to the maven central repository index, which absolutely could not function without some form of incremental update.

Simply having Quartz (which is technology we already know) fire off a 30 second job every night to rebuild the Lucene index from scratch is good enough to keep day-to-day search results fresh.