Merge branch 'mbedtls-1.3' into development

* mbedtls-1.3:
  Fix typos in Changelog
  Fix macro name from wrong branch
  Fix bug in pk_parse_key()
  Fixed typos
  Updated Travis CI config for mbedtls project

Conflicts:
	include/mbedtls/ecp.h
	include/polarssl/compat-1.2.h
	include/polarssl/openssl.h
	include/polarssl/platform.h
	library/pkparse.c
	programs/pkey/mpi_demo.c
diff --git a/include/mbedtls/ecp.h b/include/mbedtls/ecp.h
index 6eac393..922d418 100644
--- a/include/mbedtls/ecp.h
+++ b/include/mbedtls/ecp.h
@@ -642,7 +642,7 @@
  * \param pub       Keypair structure holding a public key
  * \param prv       Keypair structure holding a private (plus public) key
  *
- * \return          0 if successfull (keys are valid and match), or
+ * \return          0 if successful (keys are valid and match), or
  *                  MBEDTLS_ERR_ECP_BAD_INPUT_DATA, or
  *                  a MBEDTLS_ERR_ECP_XXX or MBEDTLS_ERR_MPI_XXX code.
  */