#7 Implement Lucene search into wCMF

[Niko]

Zend Framework (ZF) provides a stand-alone usable implementation of the Lucene search engine, known for good search results and flexible search requests. This should be implemented into wCMF.

I think of the following search possibilities:
* Global search: "Give me every object containing "Hello" in any field"
* Type-wise search: "Give me every ChiGoal containing "Hello" in any field"
* Special search "Give me every ChiGoal containing "Hello" in field name and status = "accepted"