v0.3.0-alpha

Breaking changes

• feat!: Add TypeFinder class to find subtypes that implement the contract. (#14, #18)
  Decouple type finder from plugin loader
• refactor!: Add .dll extension when the plugin name does not have it. (#19 , #20)

Other changes

• test: Add test project. (#1, #13)
• test: Add tests for plug-in loader. (#17, #21)
• refactor: Add descriptive messages to validations of PluginAttribute. (#24, #25)