Add invopop/jsonschema fork

vendor/github.com/wk8/go-ordered-map/v2/README.md

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+[![Go Reference](https://pkg.go.dev/badge/github.com/wk8/go-ordered-map/v2.svg)](https://pkg.go.dev/github.com/wk8/go-ordered-map/v2)
+[![Build Status](https://circleci.com/gh/wk8/go-ordered-map.svg?style=svg)](https://app.circleci.com/pipelines/github/wk8/go-ordered-map)
+
+# Golang Ordered Maps
+
+Same as regular maps, but also remembers the order in which keys were inserted, akin to [Python's `collections.OrderedDict`s](https://docs.python.org/3.7/library/collections.html#ordereddict-objects).
+
+It offers the following features:
+* optimal runtime performance (all operations are constant time)
+* optimal memory usage (only one copy of values, no unnecessary memory allocation)
+* allows iterating from newest or oldest keys indifferently, without memory copy, allowing to `break` the iteration, and in time linear to the number of keys iterated over rather than the total length of the ordered map
+* supports any generic types for both keys and values. If you're running go < 1.18, you can use [version 1](https://github.com/wk8/go-ordered-map/tree/v1) that takes and returns generic `interface{}`s instead of using generics
+* idiomatic API, akin to that of [`container/list`](https://golang.org/pkg/container/list)
+* support for JSON and YAML marshalling
+
+## Documentation
+
+[The full documentation is available on pkg.go.dev](https://pkg.go.dev/github.com/wk8/go-ordered-map/v2).
+
+## Installation
+```bash
+go get -u github.com/wk8/go-ordered-map/v2
+```
+
+Or use your favorite golang vendoring tool!
+
+## Supported go versions
+
+Go >= 1.18 is required to use version >= 2 of this library, as it uses generics.
+
+If you're running go < 1.18, you can use [version 1](https://github.com/wk8/go-ordered-map/tree/v1) instead.
+
+## Example / usage
+
+```go
+package main
+
+import (
+	"fmt"
+
+	"github.com/wk8/go-ordered-map/v2"
+)
+
+func main() {
+	om := orderedmap.New[string, string]()
+
+	om.Set("foo", "bar")
+	om.Set("bar", "baz")
+	om.Set("coucou", "toi")
+
+	fmt.Println(om.Get("foo"))          // => "bar", true
+	fmt.Println(om.Get("i dont exist")) // => "", false
+
+	// iterating pairs from oldest to newest:
+	for pair := om.Oldest(); pair != nil; pair = pair.Next() {
+		fmt.Printf("%s => %s\n", pair.Key, pair.Value)
+	} // prints:
+	// foo => bar
+	// bar => baz
+	// coucou => toi
+
+	// iterating over the 2 newest pairs:
+	i := 0
+	for pair := om.Newest(); pair != nil; pair = pair.Prev() {
+		fmt.Printf("%s => %s\n", pair.Key, pair.Value)
+		i++
+		if i >= 2 {
+			break
+		}
+	} // prints:
+	// coucou => toi
+	// bar => baz
+}
+```
+
+An `OrderedMap`'s keys must implement `comparable`, and its values can be anything, for example:
+
+```go
+type myStruct struct {
+	payload string
+}
+
+func main() {
+	om := orderedmap.New[int, *myStruct]()
+
+	om.Set(12, &myStruct{"foo"})
+	om.Set(1, &myStruct{"bar"})
+
+	value, present := om.Get(12)
+	if !present {
+		panic("should be there!")
+	}
+	fmt.Println(value.payload) // => foo
+
+	for pair := om.Oldest(); pair != nil; pair = pair.Next() {
+		fmt.Printf("%d => %s\n", pair.Key, pair.Value.payload)
+	} // prints:
+	// 12 => foo
+	// 1 => bar
+}
+```
+
+Also worth noting that you can provision ordered maps with a capacity hint, as you would do by passing an optional hint to `make(map[K]V, capacity`):
+```go
+om := orderedmap.New[int, *myStruct](28)
+```
+
+You can also pass in some initial data to store in the map:
+```go
+om := orderedmap.New[int, string](orderedmap.WithInitialData[int, string](
+	orderedmap.Pair[int, string]{
+		Key:   12,
+		Value: "foo",
+	},
+	orderedmap.Pair[int, string]{
+		Key:   28,
+		Value: "bar",
+	},
+))
+```
+
+`OrderedMap`s also support JSON serialization/deserialization, and preserves order:
+
+```go
+// serialization
+data, err := json.Marshal(om)
+...
+
+// deserialization
+om := orderedmap.New[string, string]() // or orderedmap.New[int, any](), or any type you expect
+err := json.Unmarshal(data, &om)
+...
+```
+
+Similarly, it also supports YAML serialization/deserialization using the yaml.v3 package, which also preserves order:
+
+```go
+// serialization
+data, err := yaml.Marshal(om)
+...
+
+// deserialization
+om := orderedmap.New[string, string]() // or orderedmap.New[int, any](), or any type you expect
+err := yaml.Unmarshal(data, &om)
+...
+```
+
+## Alternatives
+
+There are several other ordered map golang implementations out there, but I believe that at the time of writing none of them offer the same functionality as this library; more specifically:
+* [iancoleman/orderedmap](https://github.com/iancoleman/orderedmap) only accepts `string` keys, its `Delete` operations are linear
+* [cevaris/ordered_map](https://github.com/cevaris/ordered_map) uses a channel for iterations, and leaks goroutines if the iteration is interrupted before fully traversing the map
+* [mantyr/iterator](https://github.com/mantyr/iterator) also uses a channel for iterations, and its `Delete` operations are linear
+* [samdolan/go-ordered-map](https://github.com/samdolan/go-ordered-map) adds unnecessary locking (users should add their own locking instead if they need it), its `Delete` and `Get` operations are linear, iterations trigger a linear memory allocation