Added global version to DocumentTableDAO
sample_data.sql working

fixed #67
plus clean script to delete all rows in all tables
Graph object related to itself fix

Described in TextAn/Documentation/MoM/2014-07-29.txt
Merge remote-tracking branch 'origin/db-hibernate2' into server-impl

Conflicts:
	Data/src/main/java/cz/cuni/mff/ufal/textan/data/repositories/dao/IDocumentTableDAO.java
Added throwings of document changed exception