License clarification

[AlanCarriou]

The current LICENSE.txt contains the "templated" Apache 2.0 text, still with unreplaced "[yyyy] [name of copyright owner]" and the "APPENDIX: How to apply the Apache License to your work". Can you fix that ?

Furthermore, the User Guide at https://www.beanit.com/asn1/user-guide/ states "The generated Java classes may be put under a license of your choice". This exception relating to the Derivative Work should also be stated in the LICENSE.txt for clarity and comprehensiveness.