Unpublish speclets (dotnet#31737)

* remove merged specs

The following features have been merged into the standard:

- local functions
- throw expressions
- readonly struct

The PR removes those speclets from the build and redirects traffic to the best location in the spec.

* add redirections to speclets

* throw-expression is singular.

Author: BillWagner

.openpublishing.redirection.csharp.json

@@ -8,10 +8,22 @@
             "source_path_from_root": "/_csharplang/proposals/csharp-7.0/digit-separators.md",
             "redirect_url": "/dotnet/csharp/language-reference/language-specification/lexical-structure#6453-integer-literals"
         },
+        {
+            "source_path_from_root": "/_csharplang/proposals/csharp-7.0/local-functions.md",
+            "redirect_url": "/dotnet/csharp/language-reference/language-specification/statements.md#1264-local-function-declarations"
+        },
+        {
+            "source_path_from_root": "/_csharplang/proposals/csharp-7.0/throw-expression.md",
+            "redirect_url": "/dotnet/csharp/language-reference/language-specification/expressions.md#1115-the-throw-expression-operator"
+        },
         {
             "source_path_from_root": "/_csharplang/proposals/csharp-7.2/private-protected.md",
             "redirect_url": "/dotnet/csharp/language-reference/language-specification/classes.md#1436-access-modifiers"
         },
+        {
+            "source_path_from_root": "/_csharplang/proposals/csharp-7.2/readonly-struct.md",
+            "redirect_url": "/dotnet/csharp/language-reference/language-specification/structs.md#1524-struct-interfaces"
+        },
         {
             "source_path_from_root": "/_csharplang/proposals/csharp-7.3/leading-digit-separator.md",
             "redirect_url": "/dotnet/csharp/language-reference/language-specification/lexical-structure#6453-integer-literals"

docfx.json

@@ -52,7 +52,9 @@
                     "csharp-7.0/binary-literals.md",
                     "csharp-7.0/digit-separators.md",
                     "csharp-7.0/expression-bodied-everything.md",
+                    "csharp-7.0/local-functions.md",
                     "csharp-7.0/ref-locals-returns.md",
+                    "csharp-7.0/throw-expression.md",
                     "csharp-7.0/tuples.md",
                     "csharp-7.0/value-task.md",
                     "csharp-7.2/leading-separator.md",
@@ -110,7 +112,10 @@
         "rules": {
             "docs-link-absolute": {
                 "exclude": [
+                    "_csharplang/proposals/csharp-7.0/local-functions.md",
+                    "_csharplang/proposals/csharp-7.0/throw-expression.md",
                     "_csharplang/proposals/csharp-7.2/private-protected.md",
+                    "_csharplang/proposals/csharp-7.2/readonly-struct.md",
                     "_csharplang/proposals/csharp-7.3/blittable.md"
                 ]
             }
@@ -602,9 +607,7 @@
                 "_csharpstandard/standard/Bibliography.md": "Bibliography",
 
                 "_csharplang/proposals/csharp-7.0/pattern-matching.md": "Pattern matching",
-                "_csharplang/proposals/csharp-7.0/local-functions.md": "Local functions",
                 "_csharplang/proposals/csharp-7.0/out-var.md": "Out variable declarations",
-                "_csharplang/proposals/csharp-7.0/throw-expression.md": "Throw expressions",
                 "_csharplang/proposals/csharp-7.0/binary-literals.md": "Binary literals",
                 "_csharplang/proposals/csharp-7.0/digit-separators.md": "Digit separators",
                 "_csharplang/proposals/csharp-7.0/task-types.md": "Async task types",
@@ -742,9 +745,7 @@
                 "_csharpstandard/standard/Bibliography.md": "This appendix lists external standards referenced in this specification.",
 
                 "_csharplang/proposals/csharp-7.0/pattern-matching.md": "This feature specification describes the pattern matching featues added in C# 7.0. Note that future releases built on this initial set of features.",
-                "_csharplang/proposals/csharp-7.0/local-functions.md": "This feature specification describes local functions, which are functions that are embedded in another method or function.",
                 "_csharplang/proposals/csharp-7.0/out-var.md": "This feature specification describes syntax enhancements that enable declaring 'out' variables in the expression where they are used.",
-                "_csharplang/proposals/csharp-7.0/throw-expression.md": "This feature specification describes syntax enhancements that allow 'throw' to be either an expression or a statement.",
                 "_csharplang/proposals/csharp-7.0/binary-literals.md": "This feature specification describes the syntax to declare binary literals for integral constants.",
                 "_csharplang/proposals/csharp-7.0/digit-separators.md": "This feature specification describes the syntax to allow separators between groups of digits in numeric literals.",
                 "_csharplang/proposals/csharp-7.0/task-types.md": "This feature specification describes the syntax to support async return types that match a pattern, rather than restricting them to Task.",

docs/csharp/toc.yml

@@ -1344,12 +1344,8 @@ items:
       items:
       - name: Pattern matching
         href: ../../_csharplang/proposals/csharp-7.0/pattern-matching.md
-      - name: Local functions
-        href: ../../_csharplang/proposals/csharp-7.0/local-functions.md
       - name: Out variable declarations
         href: ../../_csharplang/proposals/csharp-7.0/out-var.md
-      - name: Throw expressions
-        href: ../../_csharplang/proposals/csharp-7.0/throw-expression.md
       - name: Async task types
         href: ../../_csharplang/proposals/csharp-7.0/task-types.md
     - name: C# 7.1 features