Support adding license header for kotlin files without package name (#1263)

Author: nedtwigg

Diff for: CHANGES.md

@@ -12,6 +12,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 ## [Unreleased]
 ### Added
 * Clang and Black no longer break the build when the binary is unavailable, if they will not be run during that build ([#1257](https://github.com/diffplug/spotless/pull/1257)).
+* License header support for Kotlin files without `package` or `@file` but do at least have `import` ([#1263](https://github.com/diffplug/spotless/pull/1263)).
 
 ## [2.27.0] - 2022-06-30
 ### Added

Diff for: lib/src/main/java/com/diffplug/spotless/kotlin/KotlinConstants.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 DiffPlug
+ * Copyright 2016-2022 DiffPlug
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,7 +18,7 @@
 public final class KotlinConstants {
 
 	// '^' is prepended to the regex in LICENSE_HEADER_DELIMITER later in FormatExtension.licenseHeader(String, String)
-	public static final String LICENSE_HEADER_DELIMITER = "(package |@file)";
+	public static final String LICENSE_HEADER_DELIMITER = "(package |@file|import )";
 
 	private KotlinConstants() {}
 }

Diff for: plugin-gradle/CHANGES.md

@@ -5,6 +5,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 ## [Unreleased]
 ### Added
 * Clang and Black no longer break the build when the binary is unavailable, if they will not be run during that build ([#1257](https://github.com/diffplug/spotless/pull/1257)).
+* License header support for Kotlin files without `package` or `@file` but do at least have `import` ([#1263](https://github.com/diffplug/spotless/pull/1263)).
 ### Fixed
 * Warnings about missing `Task#usesService` for Gradle 8.0 ([#1262](https://github.com/diffplug/spotless/pull/1262) fixes [#1260](https://github.com/diffplug/spotless/issues/1260))
 

Diff for: plugin-maven/CHANGES.md

@@ -5,6 +5,7 @@ We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (
 ## [Unreleased]
 ### Added
 * Clang and Black no longer break the build when the binary is unavailable, if they will not be run during that build ([#1257](https://github.com/diffplug/spotless/pull/1257)).
+* License header support for Kotlin files without `package` or `@file` but do at least have `import` ([#1263](https://github.com/diffplug/spotless/pull/1263)).
 
 ## [2.23.0] - 2022-06-30
 ### Added