Merge branch 'master' of https://github.com/math1man/wikapidia

Conflicts:
	wikapidia-core/src/main/java/org/wikapidia/core/dao/ArticleDao.java
	wikapidia-core/src/main/java/org/wikapidia/core/dao/ConceptDao.java
Corrected for some potential null pointer exceptions
my update