Add disableSniHostCheck property to TLS and SSL configuration classes

[sleberknight]

Dropwizard 3.0 added the disableSniHostCheck option with a default value of false, meaning it enables SNI checking by default. While this is good, we need to support services that cannot yet enable strict SNI checking.

So, we need to add this property to our own TLS and SSL configuration classes. The default should, like Dropwizard, be false (so strict security is the default), but also permit changing it to true (so SNI checking is disabled).

• Add disableSniHostCheck to TlsContextConfiguration
• Add disableSniHostCheck to SSLContextConfiguration
• Add disableSniHostCheck to SimpleSSLContextFactory ⁽¹⁾
• Ensure the conversion methods (toTlsContextConfiguration and toSslContextConfiguration) include the disableSniHostCheck property
• Mention in the TlsContextConfiguration#toDropwizardTlsConfiguration method that the disableSniHostCheck property does not exist in Dropwizard's TlsConfiguration class, so it is ignored.
• Mention in the TlsContextConfiguration#fromDropwizardTlsConfiguration method that the disableSniHostCheck property does not exist in Dropwizard's TlsConfiguration class, so we can't set a value from it, and that we are defaulting it to false (which enables SNI checking) because that is the more secure option.

I think these are all the things that must be changed, but when implementing there might be more. In that case, they should be added to the above list.

Notes:

1. SimpleSSLContextFactory has telescoping constructors in addition to a builder, so we need to decide whether to add disableSniHostCheck only to the builder, or to also add yet another ugly constructor. We could also choose to deprecate those constructors, since we really want people using the builder anyway.

[sleberknight]

For now, I added a new constructor, which becomes the "all-args" constructor. Deprecating and removal of these telescoping constructors should be done separately, if and when we think it makes sense.