Client Side Authentication Added

[MuniekMg]

Added client certificate for SSL Client Side Authentication with a few methods to obtain it by various of inits.

[ghost]

@daltoniam can you check it?

[daltoniam]

Looks good! I released a new version for Swift 4.1 support and that appears to created a conflict 😞. A few things I might suggest changing with the conflict updated:

• No print statements. Those errors should be bubbled up so we can return it to the user.
• I think we can remove the useSSLClientAuthentication. The optional sslClientCertificate I think should suffice.

Again looks great, just a few small things 😄.

[MuniekMg]

@daltoniam All Done! :)

[fsuc]

Thanks for this pull request. Can we add another initializer to pass data and password ?

[MuniekMg]

@fsuc I think it's question to owner @daltoniam

[AdamMak]

Any updates on when this is likely to be approved? Would really like to have this added to Starscream as I require this for my current project.

[sum98044]

me too. client certificate authentication is getting popular.
It would be great it can be approved.

[pioole]

+1

[daltoniam]

I'm finally gonna merge this 😄. I still need to do some testing, but I'm going to do that apart of my 4.0.0 release with the Network.framework. Great work and sorry about the delay!