Preserving order of enabled cipher suites and enabled protocols

[patrick-peer]

This patch preserves the order of cipher suites, set with Context.getParameters().add("enabledCipherSuites", "space separated list of cipher suites"). While usually not that important, the fix also covers the parameter "enabledProtocols".

I am aware that Restlet is not actively maintained any more. I created this pull request for others in the community that might be able to make use of it.