Add initial RFC document (endpoints 2.0) (#1637)

* Add initial RFC document

* CR feedback

* RFC updates

* Rename doc, add to summary / overview

* Apply suggestions from code review

Co-authored-by: John DiSanti <jdisanti@amazon.com>

* Update design/src/rfcs/rfc_0020_endpoints_20.md

Co-authored-by: Zelda Hessler <zhessler@amazon.com>

* RFC updates

* More cleanups

* Delete old file

* rfc updates

* delete old file

* fix merge

Co-authored-by: John DiSanti <jdisanti@amazon.com>
Co-authored-by: Zelda Hessler <zhessler@amazon.com>

design/src/SUMMARY.md

@@ -49,6 +49,7 @@
   - [RFC-0024: RequestID](./rfcs/rfc0024_request_id.md)
   - [RFC-0025: Constraint traits](./rfcs/rfc0025_constraint_traits.md)
   - [RFC-0026: Client Crate Organization](./rfcs/rfc0026_client_crate_organization.md)
+  - [RFC-0027: Endpoints 2.0](./rfcs/rfc0027_endpoints_20.md)
 
 - [Contributing](./contributing/overview.md)
   - [Writing and debugging a low-level feature that relies on HTTP](./contributing/writing_and_debugging_a_low-level_feature_that_relies_on_HTTP.md)

design/src/rfcs/overview.md

@@ -36,3 +36,4 @@
 - [RFC-0024: RequestID](./rfc0024_request_id.md)
 - [RFC-0025: Constraint traits](./rfc0025_constraint_traits.md)
 - [RFC-0026: Client Crate Organization](./rfc0026_client_crate_organization.md)
+- [RFC-0027: Endpoints 2.0](./rfc0027_endpoints_20.md)

rust-runtime/aws-smithy-types/src/endpoint.rs

@@ -10,6 +10,7 @@ use std::collections::HashMap;
 
 type MaybeStatic = Cow<'static, str>;
 
+/* ANCHOR: endpoint */
 /// Smithy Endpoint Type
 ///
 /// Generally, this type should not be used from user code
@@ -20,6 +21,8 @@ pub struct Endpoint {
     properties: HashMap<MaybeStatic, Document>,
 }
 
+/* ANCHOR_END: endpoint */
+
 #[allow(unused)]
 impl Endpoint {
     /// Returns the URL of this endpoint