Update changes preparing for 2.2.0 release

CHANGES

@@ -1,6 +1,41 @@
 Changelog
 
-2.2.0-pre (This version)
+2.3.0-pre (This version)
+
+Major changes
+
+A fuzzer was added to the project based on libFuzzer. This is run as part of Google oss-fuzz, the current status can be found at https://oss-fuzz-build-logs.storage.googleapis.com/index.html#libsrtp . Details available in PR #442 and issue #393.
+
+CMake support was added as an alternative build system. This was primarily added to replace the Visual Studio project files currently checked in but has been extend to support building on all platforms. Initial PR #449 and #455 but has been support has been continuously improved. 
+
+NSS support for crypto backend was added. This is can be used as an alternative to openssl. Initial PR #413 but there has been numerous improvements.
+
+
+PR #474 - Add flag to disable pcap dependency when build test apps.
+
+PR #472 - Add ci builds for ios and android.
+
+PR #463 - problem on srtp_aes_icm_openssl_encrypt.
+
+PR #471 - Allow the pcap file to be read from a physical file.
+
+PR #457 - Fix docs crypto_policy_* -> srtp_crypto_policy_* .
+
+PR #452 - crypto/cipher: Reset the EVP_CIPHER_CTX structure before each test.
+
+PR #444 - Extend rtp_ecoder to support RTCP and multiplexed SSRC's.
+
+PR #443 - rtp_decoder avoid crash when no packets found.
+
+PR #429 - Rand for test only.
+
+PR #421 - Fix GCM IV logging.
+
+PR #415 - Fixes unaligned trailer access.
+
+PR #414 - Detect and handle broken "OPENSSL_cleanse".
+
+2.2.0
 
 Major changes