Add lazyDeployment flag to split operators

[bknasmueller]

By defining lazy-deployment to be TRUE or FALSE, Pathfinder will deploy all fallback paths' operators at initialisation or at their activation, respectively.

Example:

$split = Split($step1) {
   lazyDeployment = false,
   pathOrder = $step2a $step2b
 }

here, Pathfinder will deploy all operators in the paths $step2a and $step2b at topology initialisation time.

$split = Split($step1) {
   lazyDeployment = true,
   pathOrder = $step2a $step2b
 }

Here, pathfinder will first deploy the operators of path $step2a. Only if a fault in that path is detected, the operators of path $step2b are deployed and actively used.