Allow setting access log settings for Api Gateway in stage specific config

My organization requires all API Gateway resource to have API Gateway Access Logging enabled. In order for me to advocate successfully for chalice usage throughout our enterprise, we need to eliminate the manual step of setting up access logs post deployment.

Start by tracing how Chalice represents stage-specific configuration and how it deploys API Gateway stages. Done means access logging can be enabled through configuration for each stage, so deployments no longer require a manual post-deployment step.

Written by the indexing model from the issue text.