0.0.3

• Introduce abstract classes PolicyConfigurator<TPolicy> and PolicyBuilder<TPolicy, TConfigurator>.
• Update Microsoft nuget packages.
• Add Advanced Usage section to README.
• Move the RetryLoggingErrorProcessor to Shared.csproj.
• Add ConfiguratorDemo.csproj to Samples.sln.
• Create Shared.csproj in Samples and move SomeException into it.
• Move Samples.csproj into a new Intro folder and rename it to `Intro.csproj