* add copying of aggregation mode for conversion from 50 to 30 
* add test for Observation conversion from 10 to 40
* add procedures conversion form dstu2 to r4
* add medication conversion from dstu2 to r4
* Adding Maven exec to test validation cli jar
* Validation of cardinality on address-line elements containing pattern elements fixed
* Ensure that validator creates errors on example urls by default
* Add -allow-example-urls option to the validator