GH-266 Consolidated Adapter infrastructure

- Moved common logic into a new AbstractSpringFunctionAdapterInitializer
- Modified Azure and AWS request handlers to extend from it
- Deprecated both AzureSpringFunctionInitializer and SpringFunctionInitializer(AWS)

Resolves #266

spring-cloud-function-samples/function-sample-azure/pom.xml

@@ -55,7 +55,7 @@
 			<dependency>
 				<groupId>org.springframework.cloud</groupId>
 				<artifactId>spring-cloud-function-dependencies</artifactId>
-				<version>2.0.0.BUILD-SNAPSHOT</version>
+				<version>2.1.0.BUILD-SNAPSHOT</version>
 				<type>pom</type>
 				<scope>import</scope>
 			</dependency>