Update LICENSE and PQ readme

LICENSE

@@ -219,6 +219,5 @@ The following components are provided under the MIT License. See project link fo
 
     SIKE
       -> s2n/pq-crypto/sike/LICENSE.txt
-
-
-
+    BIKE
+      -> s2n/pq-crypto/bike/LICENSE

pq-crypto/README.md

@@ -25,5 +25,12 @@ See [this s2n issue](https://github.com/awslabs/s2n/issues/904) for more up-to-d
 ## SIKE (Supersingular Isogeny Key Encapsulation)
 The code in the pq-crypto/sike directory was taken from the [round 1 nist submission](https://csrc.nist.gov/CSRC/media/Projects/Post-Quantum-Cryptography/documents/round-1/submissions/SIKE.zip).
 s2n uses the reference implementation to ensure maximum comparability and ease of review. The known answer tests are
-[here](https://github.com/awslabs/s2n/blob/master/tests/unit/s2n_sike_p503_kat_test.c) and use the known answer file
-from the SIKEp503 round 1 submission.
+[here](https://github.com/awslabs/s2n/blob/master/tests/unit/s2n_sike_p503_kat_test.c) and use the PQCkemKAT_434.rsp file
+from the above SIKE.zip.
+
+## BIKE (Bit Flipping Key Encapsulation)
+The code in the pq-crypto/bike directory was taken from the [additional implementation](https://bikesuite.org/files/round2/add-impl/Additional_Implementation.2019.03.30.zip).
+s2n uses the "additional implementation" which ensures constant time decapsulation, does not use any external libraries
+besides libcrypto, and does not depend on any specific hardware instructions to ensure maximum comparability and ease of
+review. The known answer tests are [here](https://github.com/awslabs/s2n/blob/master/tests/unit/s2n_bike1_l1_kat_test.c)
+and use the BIKE1_L1.const.kat from the above Additional_Implementation.2019.03.30.zip.