Remove appendix from APACHE license

This change is to be consistent with rust-lang/rust.
Their change was made in December 2019. The PR over there: [Remove appendix from LICENCE-APACHE](rust-lang/rust#65141)

LICENSE-APACHE

@@ -173,29 +173,4 @@ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
    incurred by, or claims asserted against, such Contributor by reason
    of your accepting any such warranty or additional liability.
 
-END OF TERMS AND CONDITIONS
-
-APPENDIX: How to apply the Apache License to your work.
-
-   To apply the Apache License to your work, attach the following
-   boilerplate notice, with the fields enclosed by brackets "[]"
-   replaced with your own identifying information. (Don't include
-   the brackets!)  The text should be enclosed in the appropriate
-   comment syntax for the file format. We also recommend that a
-   file or class name and description of purpose be included on the
-   same "printed page" as the copyright notice for easier
-   identification within third-party archives.
-
-Copyright [yyyy] [name of copyright owner]
-
-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.
+END OF TERMS AND CONDITIONS