Migrate build script to Swift

Author: kimdv

CodeGeneration/Package.swift renamed to SwiftSyntaxCLI/Package.swift

@@ -4,19 +4,19 @@ import PackageDescription
 import Foundation
 
 let package = Package(
-  name: "CodeGeneration",
+  name: "SwiftSyntaxCLI",
   platforms: [
     .macOS(.v10_15)
   ],
   products: [
-    .executable(name: "generate-swiftsyntax", targets: ["generate-swiftsyntax"])
+    .executable(name: "swift-syntax-cli", targets: ["swift-syntax-cli"])
   ],
   dependencies: [
     .package(url: "..", revision: "HEAD")
   ],
   targets: [
     .executableTarget(
-      name: "generate-swiftsyntax",
+      name: "swift-syntax-cli",
       dependencies: [
         .product(name: "SwiftSyntax", package: "swift-syntax"),
         .product(name: "SwiftSyntaxBuilder", package: "swift-syntax"),

CodeGeneration/README.md renamed to SwiftSyntaxCLI/README.md

@@ -1,20 +1,21 @@
-# Code-Generation for SwiftSyntax
+# SwiftSyntaxCLI
+
+## Code-Generation for SwiftSyntax
 
 This directory contains file to generate source code that is part of the SwiftSyntax package. If you are looking to generate Swift code yourself, you might be interested in [SwiftSyntaxBuilder](../Sources/SwiftSyntaxBuilder).
 
 Some source code inside SwiftSyntax is generated using [SwiftSyntaxBuilder](../Sources/SwiftSyntaxBuilder), a Swift library whose purpose is to generate Swift code using Swift itself. This kind of code generation is performed by the Swift package defined in this directory.
 
-This directory is a standalone package that uses HEAD of the current branch. This guarantees that when `generate-swiftsyntax` is run, it can't break its own build when run multiple times without committing. 
-This means that `CodeGeneration` will build against your latest local commit of SwiftSyntax. If you are making changes to `SwiftSyntax` that affect how code is being generated, commit your SwiftSyntax changes (pushing is not necessary) and re-generate files afterwards.
+This directory is a standalone package that uses HEAD of the current branch. This guarantees that when `generate-source-code` is run, it can't break its own build when run multiple times without committing. 
+This means that `SwiftSyntaxCLI` will build against your latest local commit of SwiftSyntax. If you are making changes to `SwiftSyntax` that affect how code is being generated, commit your SwiftSyntax changes (pushing is not necessary) and re-generate files afterwards.
 
-To re-generate the files after changing `CodeGeneration` run the `generate-swiftsyntax` 
-target of `CodeGeneration` and pass `path/to/swift-syntax/Sources` as the argument.
+To re-generate the files after changing `SwiftSyntaxCLI` run the `swift-syntax-cli` 
+target of `SwiftSyntaxCLI` and pass `path/to/swift-syntax/Sources` as the argument.
 
 On the command line, this would be
 ```bash
-swift run --package-path CodeGeneration generate-swiftsyntax Sources
+swift run --package-path SwiftSyntaxCLI swift-syntax-cli generate-source-code Sources
 ```
 
-Or if you open the `CodeGeneration` package in Xcode, you can add the 
-`generate-swift syntax ../Sources` arguments using Product -> Scheme -> Edit Scheme…
-
+Or if you open the `SwiftSyntaxCLI` package in Xcode, you can add the 
+`swift-syntax-cli generate-source-code ../Sources` arguments using Product -> Scheme -> Edit Scheme…