Ensure only one Lucene IndexWriter is created per index.

I believe, but cannot prove, that we have multiple writers/locks on the same index.

Lock timeouts are occuring in Lucene, but "timeout" is misleading. It actually is just trying once and failing. I believe it may be due to the fact that create a new IndexWriter every time you call IndexHandle.createIndex, but have another lazy-inited IndexWriter created through getWriter.

A possible cause for this is through starting a repository in Admin, which takes you eventually to:

Caused by: org.apache.lucene.store.LockObtainFailedException: Lock obtain timed out: NativeFSLock@/data/fecru/data/var/cache/grm-margin_support/idx2/write.lock
	at org.apache.lucene.store.Lock.obtain(Lock.java:84)
	at org.apache.lucene.index.IndexWriter.init(IndexWriter.java:1066)
	at org.apache.lucene.index.IndexWriter.<init>(IndexWriter.java:888)
	at com.cenqua.fisheye.lucene.writer.DefaultIndexWriterFactory.newIndexWriter(DefaultIndexWriterFactory.java:12)

CRC-2584 is a case where this is occuring.