Extend createMethodSignature and updateMethodSignature with 'modifiers' argument

## Search Terms <!-- List of keywords you searched for before creating this issue. Write them down here so that others can find this suggestion more easily --> updateMethodSignature, createMethodSignature ## Suggestion <!-- A summary of what you'd like to see added or changed --> It should be possible to provide an array of Modifiers (or `undefined`) to the `createMethodSignature` and `updateMethodSignature` functions. ## Use Cases <!-- What do you want to use this for? What shortcomings exist with current approaches? --> When using the TypeScript compiler APIs, TypeScript provides numerous `create` and `update` functions that can be used to generate an AST, for example from Custom Transformers. However, for `MethodSignature`s, which may have modifiers such as the `static` keyword, there's no option to create or update their modifiers. This breaks [one of my libraries](https://github.com/wessberg/ts-clone-node) which sole purpose is to simply deep-clone a TypeScript node. A workaround is to manually patch the modifiers, however I hope this can be part of the function (as it is for others, like `createPropertySignature` and `updatePropertySignature`). ## Examples <!-- Show how this would be used and what the behavior would be --> ```typescript import {createMethodSignature, createNodeArray, createModifier, SyntaxKind} from "typescript"; createMethodSignature( createNodeArray([ createModifier(SyntaxKind.StaticKeyword) ]), node.typeParameters, node.parameters, node.type, node.name, node.questionToken ); ``` However, the above example would be a breaking change since the first parameter expects a NodeArray of type parameters, so an alternative solution would be to accept it as the last argument. ## Checklist My suggestion meets these guidelines: * [X] This wouldn't be a breaking change in existing TypeScript/JavaScript code * [X] This wouldn't change the runtime behavior of existing JavaScript code * [X] This could be implemented with…