support nested blueprint accessor notation

[AlanFoster]

From the OSGI spec the blueprint bean name attribute can

Syntax	Description
method ( ’.’ method)*	The property name, for example foo. The method name can consist of dot separated method names, indicating nested property access

Currently we don't support nested property access =]

[AlanFoster]

It's unlikely that this is a common used feature, so it is not needed to make a 0.1 release.
However the struts2 plugin currently supports this, so it should definitely be investigated in the future :)