Merge 'mbedtls/development' into merge-crypto-development-20190806

Conflicts and changes:
* Files that do not exist in Mbed Crypto and have changed in Mbed TLS:
  These files should not exist in Mbed Crypto. Keep them deleted.
* tests/data_files/test-ca.server1.db: new file in Mbed TLS, don't create
  it in Mbed Crypto.
* tests/data_files/rsa_pkcs1_1024_clear.pem: do create this file in
  Mbed Crypto. I don't see why it would be kept out.
* tests/data_files/Makefile: don't take any of the changes in sections
  that have been removed in Crypto. Do take in the certificate
  expiration date updates and the extra .crt.der rules (even if Crypto
  doesn't actually use those certificates: removing them would be out
  of scope of the present merge).
* tests/suites/helpers.function: consecutive additions, take
  both (order indifferent).

scripts/abi_check.py

@@ -107,7 +107,7 @@ class AbiChecker(object):
         )
         self.log.debug(worktree_output.decode("utf-8"))
         version.commit = subprocess.check_output(
-            [self.git_command, "rev-parse", worktree_rev],
+            [self.git_command, "rev-parse", "HEAD"],
             cwd=git_worktree_path,
             stderr=subprocess.STDOUT
         ).decode("ascii").rstrip()