* Adds variables to the xml. So you can say  <initial-permits>${initial.permits}</initial-permits>
 This is very useful if you want to parametrize your hazelcast configuration. The XMLConfigBuilder by default will be configured using the system properties, but one can also inject its own properties.
Merge pull request #528 from pveentjer/feature/3.0/xmlimportandvariables

Feature/3.0/xmlimportandvariables