Minor license formatting cleanup to allow GitHub to recognize our BSD…

… 3-Clause License. Move third-party licenses notice to NOTICE file.

LICENSE

@@ -1,4 +1,4 @@
-DSpace source code BSD License:
+BSD 3-Clause License
 
 Copyright (c) 2002-2021, LYRASIS.  All rights reserved.
 
@@ -13,13 +13,12 @@ notice, this list of conditions and the following disclaimer.
 notice, this list of conditions and the following disclaimer in the
 documentation and/or other materials provided with the distribution.
 
-- Neither the name DuraSpace nor the name of the DSpace Foundation
-nor the names of its contributors may be used to endorse or promote
-products derived from this software without specific prior written
-permission.
+- Neither the name of the copyright holder nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
 
 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
@@ -29,11 +28,4 @@ OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
-DAMAGE.
-
-
-DSpace uses third-party libraries which may be distributed under
-different licenses to the above. Information about these licenses
-is detailed in the LICENSES_THIRD_PARTY file at the root of the source
-tree.  You must agree to the terms of these licenses, in addition to
-the above DSpace source code license, in order to use this software.
+DAMAGE.

NOTICE

@@ -1,3 +1,13 @@
+Licenses of Third-Party Libraries
+=================================
+
+DSpace uses third-party libraries which may be distributed under
+different licenses than specified in our LICENSE file. Information
+about these licenses is detailed in the LICENSES_THIRD_PARTY file at
+the root of the source tree. You must agree to the terms of these
+licenses, in addition to the DSpace source code license, in order to
+use this software.
+
 Licensing Notices
 =================