implemented liquibase T:2h0
add liquibase.changeLogFile property

In order to get liquibase:update to run, I had to include
\<liquibase.changeLogFile\> in the list of liquibase.properties
specified in the \<properties\> section.
added liquibase.properties and change pom.xml accordingly
added liquibase.properties and change pom.xml accordingly
Add link to liquibase.propertyFile in pom.xml (See #17) T:2h00
Merge pull request #72 from jembi/Autoset_Product_creation_date_to_Collection_number_creation_date_#17

Add Liquibase to codebase