Remove dependency of System.Runtime.Serialization.dll

## Overview
* Remove assembly references to `System.Runtime.Serialization`.
* Re-implement the codes to test `DataContractAttribute` and `DataMemberAttribute` with reflection rather than static member access.
* This also may be able to apply for the branch `0.5`.

## Purpose
* The dependency of `System.Runtime.Serialization` is only for compatibility for other serializer, but this causes loading `System.Runtime.Serialization` assembly. I think this is a bit wasteful.

## Concerns
* It ran in my environment but it is not fully-tested.