refs #1

Expressions evaluate only once per iteration, this means variables modified within the loop are not re-evaluated. Moved dynamic content replacement from doExecute (evaluates only once on start) to checkCondition (evaluates each loop).
refs #2

Moving variable extraction to validateMessage function. This allows to derive from ReceiveMessageAction and do enhanced message validation before extraction and basic validation.
refs #3

Support of validation matcher expressions in message validation.
Enhanced debug output on XML validation error.
refs #4

Define complex types in testcase (core, ws) schemas for all test case actions, like it is already done for send and receive action. Defining complex types allows deriving and defining extended types, like it is already implemented for core:send and ws:send. We use an extended type of ws:send which requires derivation of ws:send which is currently not defined as complex type. All other action types are changed as well for future enhancement possibilities.

This change does not change functionality in any way.