Support application threads racing to add/remove same object about cqengine HOT 3 CLOSED

Checked in initial support to trunk. Functionality is implemented but *the API 
is not final* yet:

http://code.google.com/p/cqengine/source/browse/cqengine/trunk/src/main/java/com
/googlecode/cqengine/collection/impl/IndexedCollectionStripedImpl.java

Usage (note: API might change!): 
IndexedCollection<O> collection = CQEngine.newInstanceStriped(512);

...this would return an implementation which supports concurrent 
adding/removing of the same object.

This feature will be included in the next release, along with the recent 
support for JOINS. ETA: next few weeks. API is likely to be renamed from this 
example slightly.

Done. Available in CQEngine 1.1.0, released.

Implemented as 
http://cqengine.googlecode.com/svn/cqengine/javadoc/apidocs/com/googlecode/cqeng
ine/collection/impl/ObjectLockingIndexedCollection.html

Static factory methods added to CQEngine convenience class, to create 
object-locking instances of IndexedCollection.