Provide simpler testing of FeatureSwitch Types

#24 - API integration to support Admin UI and basic use cases. Modified the previous botched attempt (see #32) and this time allowed testing of FeatureSwitchType retrieval (AllSwitchTypes) by providing the ability to pass in a subset of selected FeatureSwitchTypes to the FemahFluentConfiguration.

- Also added link to femah logo to readme