simplify ServiceComponentList

[bollhals]

This change simplifies the ServiceComponentList by changing the way the default is handled.

Instead of using a ValueHolder and concating it at the end of the list, it's now added at the end of the list and kept track of it.

Side changes included:

• Sorted the ValueRetriever by likelyhood of usage (as we're iterating over each retriever front to back to find the one that can convert the value)
• Simplify creating the list of Retrievers/Comparers by adding a new internal ctor, this avoids the repetitive List<T>.Insert(0, ...) calls in Register.

Types of changes

• Bug fix (non-breaking change which fixes an issue).
• New feature (non-breaking change which adds functionality).
• Breaking change (fix or feature that would cause existing functionality to not work as expected).
• Performance improvement
• Refactoring (so no functional change)
• Other (docs, build config, etc)

Checklist:

• I've added tests for my code. (most of the time mandatory)
• I have added an entry to the changelog. (mandatory)
• My change requires a change to the documentation.
• I have updated the documentation accordingly.