Trnk 4140 : Substitute deprecated method call in HibernateContextDAO

removed "ConfigHelper.getResourceAsStream"  deprecatede method. 

added junit test "should_mergeDefaultRuntimeProperties()" in ContextDAOTest.java class. 
But when testing it throws  java.util.ConcurrentModificationException.
as i read in http://docs.oracle.com/javase/6/docs/api/java/util/ConcurrentModificationException.html and  http://stackoverflow.com/questions/1931180/how-do-i-synchronize-to-prevent-a-java-util-concurrentmodificationexception ,  the reason is , we change a element in a java Collection while we iterate through it . 

One possible solution would be using ConcurrentHashMap. But here we use java.util.Property. 

The other possible solution would be instead of changing the values while iterating through a collection, cache the changes and then copy them to the Collection. 

I have used the latter approach here.