Redesign Strategy, Load, and Resources data types

• CompositeStrategy should be handled as all other search strategies
  • Goal: Yaml strategy.name should indicate (Kotlin) type of strategy (implements SearchStrategy)
• Strategies should be able to handle both our scalability metrics ("demand" and "capacity")
• Load and Resource values can be simply represented as integers
• Load types and resources can be represented as before

Possible YAML representation:

execution:
  metric: demand # or "capacity"
  strategy:
    name: RestrictionSearch
    properties:
      # optional further properties
      restrictionStrategy: LowerBound
      searchStrategy: LinearSearch