Merge branch 'development' into iotssl-1260-non-blocking-ecc-restricted

* development:
  ssl-opt.sh: change expected output for large srv packet test with SSLv3
  Adapt ChangeLog
  Fix bug in SSL ticket implementation removing keys of age < 1s
  ssl-opt.sh: Add DTLS session resumption tests
  Add ChangeLog entry
  Fix typo
  Fix hmac_drbg failure in benchmark, with threading
  Remove trailing whitespace
  Remove trailing whitespace
  ssl_server2: add buffer overhead for a termination character
  Add missing large and small packet tests for ssl_server2
  Added buffer_size and response_size options for ssl-server2. Added appropriate tests.

Solving a conflict in tests/ssl-opt.sh: two set of tests were added at the
same place (just after large packets):
- restartable ECC tests (in this branch)
- server-side large packets (in development)

Resolution was to move the ECC tests after the newly added server large packet
ones.

ChangeLog

@@ -10,6 +10,18 @@ Features
      functions in ECDH and SSL (currently only implemented client-side, for
      ECDHE-ECDSA ciphersuites with TLS 1.2, including client authentication).
 
+Bugfix
+   * Fix a bug in the update function for SSL ticket keys which previously
+     invalidated keys of a lifetime of less than a 1s. Fixes #1968.
+   * Fix failure in hmac_drbg in the benchmark sample application, when
+     MBEDTLS_THREADING_C is defined. Found by TrinityTonic, #1095
+
+Changes
+   * Add tests for session resumption in DTLS.
+   * Close a test gap in (D)TLS between the client side and the server side:
+     test the handling of large packets and small packets on the client side
+     in the same way as on the server side.
+
 = mbed TLS 2.13.1 branch released 2018-09-06
 
 API Changes