code: public KeyBundle createKey(String vaultBaseUrl, String keyName, JsonWebKeyType kty) {
          return createKeyWithServiceResponseAsync(vaultBaseUrl, keyName, kty).toBlocking().single().body();
      }
docs: Creates a new key, stores it, then returns key parameters and attributes to the client.
  The create key operation can be used to create any key type in Azure Key Vault. If the named key already exists, Azure Key Vault creates a new version of the key. It requires the keys/create permission.
  
  @param vaultBaseUrl The vault name, for example https://myvault.vault.azure.net.
  @param keyName The name for the new key. The system will generate the version name for the new key.
  @param kty The type of key to create. For valid values, see JsonWebKeyType. Possible values include: 'EC', 'EC-HSM', 'RSA', 'RSA-HSM', 'oct'
  @throws IllegalArgumentException thrown if parameters fail the validation
  @throws KeyVaultErrorException thrown if the request is rejected by server
  @throws RuntimeException all other wrapped checked exceptions if the request fails to be sent
  @return the KeyBundle object if successful.