Annotate source files with license and copyright info

[ronaldbowers]

Each source file needs to be annotated with the Apache License block and a copyright notice. This should be easy with IntelliJ.

[canthurt]

@ronaldbowers to clarify, is this the correct header:

/*

• Copyright (c) 2023
• United States Government as represented by the U.S. Army DEVCOM Analysis Center.
• Licensed under the Apache License, Version 2.0 (the "License");
• you may not use this file except in compliance with the License.
• You may obtain a copy of the License at
• http://www.apache.org/licenses/LICENSE-2.0
• Unless required by applicable law or agreed to in writing, software
• distributed under the License is distributed on an "AS IS" BASIS,
• WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
• See the License for the specific language governing permissions and
• limitations under the License.
  */