Add Unit Test and Integration Test for SSL support feature

This commit added UT and IT to cover the SSL support featre. Namely:
  * Introduced RestAssured as the client to simplify the testing code
  * Create a set of PKI and CA for testing different combinations of keystore and turststore in local environment
  * Added UT to cover HttpsSettings, WireMockConfiguration and CommandLineOptions class
  * Added IT to cover the case where WireMock server quires client auth