COPYRIGHT file incorrectly references LGPL license

The https://github.com/ModeShape/modeshape/blob/master/modeshape-jca-rar/src/main/assembly/COPYRIGHT.txt file incorrectly mentions the LGPL license, even though we've moved to the Apache License 2.0 years ago.

This needs to be fixed, and we need to verify that LGPL is no longer referenced in any other files.