Add deprecated and writeOnly as part of schema (#125)

Author: tstirrat15

README.md

@@ -90,6 +90,9 @@ These tags can be used:
 * [`example`](https://json-schema.org/draft/2020-12/json-schema-validation.html#name-examples), a scalar value that matches type of parent property, for an array it is applied to items
 * [`examples`](https://json-schema.org/draft/2020-12/json-schema-validation.html#name-examples), a JSON array value
 * [`const`](https://json-schema.org/draft/2020-12/json-schema-validation.html#rfc.section.6.1.3), can be scalar or JSON value
+* [`deprecated`](https://json-schema.org/draft/2020-12/json-schema-validation#name-deprecated), boolean
+* [`readOnly`](https://json-schema.org/draft/2020-12/json-schema-validation#name-deprecated), boolean
+* [`writeOnly`](https://json-schema.org/draft/2020-12/json-schema-validation#name-deprecated), boolean
 * [`pattern`](https://json-schema.org/draft-04/json-schema-validation.html#rfc.section.5.2.3), string
 * [`format`](https://json-schema.org/draft-04/json-schema-validation.html#rfc.section.7), string
 * [`multipleOf`](https://json-schema.org/draft-04/json-schema-validation.html#rfc.section.5.1.1), float > 0
@@ -274,4 +277,4 @@ s, err := r.Reflect(My{}, jsonschema.InterceptProp(func(params jsonschema.Interc
 
     return nil
 }))
-```
+```

entities.go

@@ -1161,13 +1161,6 @@ func (r *Reflector) walkProperties(v reflect.Value, parent *Schema, rc *ReflectC
 			return err
 		}
 
-		deprecated := false
-		if err := refl.ReadBoolTag(field.Tag, "deprecated", &deprecated); err != nil {
-			return err
-		} else if deprecated {
-			propertySchema.WithExtraPropertiesItem("deprecated", true)
-		}
-
 		if !rc.SkipNonConstraints {
 			if err := reflectExamples(rc, &propertySchema, field); err != nil {
 				return err