ProjectNodes: Refactor runConfigurationsFor()

Rename to runConfigurations() and remove the node argument which is
available as 'this'. Adjust const-ness of node argument in
RunConfigurationFactory::runConfigurationsForNode

Change-Id: Icb63e96a305152f90135a2656536de2581faafaf
Reviewed-by: Daniel Teske <daniel.teske@digia.com>