Base template activity

[lmagyar]

Currently workflows are transaction scripts. Make them DSL.
In a template activity you can specify one or more activities as arguments (like the try/catch/finally arguments in TryCatchFinally activity).
And a body, where you can use these arguments.
This way you can build template activities based on this base like:

• "execute this activity in a loop in case of exceptions"
• "wait for this incoming request with a timeout and throw exception when it expires"