Make disclaimer about this not being guarantees a lot more visible

People continue to miss it, and the old disclaimer is easily overlooked
when skimming. Make sure that it's more visible.

Additionally, rename all the pages to more clearly say **suggestions**,
making it more visible that those are **not** **guarantees**.

Author: Noratrieb

reference/src/SUMMARY.md

@@ -2,15 +2,15 @@
 
 - [Introduction](./introduction.md)
 - [Glossary](./glossary.md)
-- [Data layout](./layout.md)
-  - [Structs and tuples](./layout/structs-and-tuples.md)
-  - [Scalars](./layout/scalars.md)
-  - [Enums](./layout/enums.md)
-  - [Unions](./layout/unions.md)
-  - [Pointers](./layout/pointers.md)
+- [Data layout suggestions](./layout.md)
+  - [Structs and tuples layout suggestions](./layout/structs-and-tuples.md)
+  - [Scalar layout suggestions](./layout/scalars.md)
+  - [Enum layout suggestions](./layout/enums.md)
+  - [Union layout suggestions](./layout/unions.md)
+  - [Pointer layout suggestions](./layout/pointers.md)
   - [Function pointers](./layout/function-pointers.md)
   - [Arrays and Slices](./layout/arrays-and-slices.md)
-  - [Packed SIMD vectors](./layout/packed-simd-vectors.md)
+  - [Packed SIMD vectors layout suggestions](./layout/packed-simd-vectors.md)
 - [Validity](./validity.md)
   - [Unions](./validity/unions.md)
   - [Function Pointers](./validity/function-pointers.md)

reference/src/layout/enums.md

@@ -1,11 +1,11 @@
-# Layout of Rust `enum` types
-
-**Disclaimer:** Some parts of this section were decided in RFCs, but
-others represent the consensus from issue [#10]. The text will attempt
-to clarify which parts are "guaranteed" (owing to the RFC decision)
-and which parts are still in a "preliminary" state, at least until we
-start to open RFCs ratifying parts of the Unsafe Code Guidelines
-effort.
+# Suggested Layout of Rust `enum` types
+
+<div class="warning">
+
+This page describes an opinion on what the original unsafe-code-guidelines _wanted_
+layout to be from [#10]. **It does not reflect current or future Rust guarantees**.
+
+</div>
 
 **Note:** This document has not yet been updated to
 [RFC 2645](https://github.com/rust-lang/rfcs/blob/master/text/2645-transparent-unions.md).

reference/src/layout/packed-simd-vectors.md

@@ -1,8 +1,11 @@
-# Layout of packed SIMD vectors
+# Suggested Layout of packed SIMD vectors
 
-**Disclaimer:** This chapter represents the consensus from issue
-[#38]. The statements in here are not (yet) "guaranteed"
-not to change until an RFC ratifies them.
+<div class="warning">
+
+This page describes an opinion on what the original unsafe-code-guidelines _wanted_
+layout to be from [#38]. **It does not reflect current or future Rust guarantees**.
+
+</div>
 
 [#38]: https://github.com/rust-rfcs/unsafe-code-guidelines/issues/38
 

reference/src/layout/pointers.md

@@ -1,10 +1,11 @@
-# Layout of reference and pointer types
+# Suggested Layout of reference and pointer types
 
-**Disclaimer:** Everything this section says about pointers to dynamically sized
-types represents the consensus from issue [#16], but has not been stabilized
-through an RFC. As such, this is preliminary information.
+<div class="warning">
 
-[#16]: https://github.com/rust-rfcs/unsafe-code-guidelines/issues/16
+This page describes an opinion on what the original unsafe-code-guidelines _wanted_
+layout to be from [#16]. **It does not reflect current or future Rust guarantees**.
+
+</div>
 
 ### Terminology
 

reference/src/layout/scalars.md

@@ -1,8 +1,11 @@
-# Layout of scalar types
+# Suggested  Layout of scalar types
 
-**Disclaimer:** This chapter represents the consensus from issue
-[#9].  The statements in here are not (yet) "guaranteed"
-not to change until an RFC ratifies them.
+<div class="warning">
+
+This page describes an opinion on what the original unsafe-code-guidelines _wanted_
+layout to be from [#9]. **It does not reflect current or future Rust guarantees**.
+
+</div>
 
 This documents the memory layout and considerations for `bool`, `char`, floating
 point types (`f{32, 64}`), and integral types (`{i,u}{8,16,32,64,128,size}`).

reference/src/layout/structs-and-tuples.md

@@ -1,8 +1,11 @@
-# Layout of structs and tuples
+# Suggested Layout of structs and tuples
 
-**Disclaimer:** This chapter represents the consensus from issues
-[#11] and [#12].  The statements in here are not (yet) "guaranteed"
-not to change until an RFC ratifies them.
+<div class="warning">
+
+This page describes an opinion on what the original unsafe-code-guidelines _wanted_
+layout to be from [#11] and [#12]. **It does not reflect current or future Rust guarantees**.
+
+</div>
 
 [#11]: https://github.com/rust-rfcs/unsafe-code-guidelines/issues/11
 [#12]: https://github.com/rust-rfcs/unsafe-code-guidelines/issues/12

reference/src/layout/unions.md

@@ -1,11 +1,11 @@
-# Layout of unions
+# Suggested Layout of unions
 
-**Disclaimer:** This chapter represents the consensus from issue
-[#13].  The statements in here are not (yet) "guaranteed"
-not to change until an RFC ratifies them.
+<div class="warning">
 
-**Note:** This document has not yet been updated to
-[RFC 2645](https://github.com/rust-lang/rfcs/blob/master/text/2645-transparent-unions.md).
+This page describes an opinion on what the original unsafe-code-guidelines _wanted_
+layout to be from [#13]. **It does not reflect current or future Rust guarantees**.
+
+</div>
 
 [#13]: https://github.com/rust-rfcs/unsafe-code-guidelines/issues/13