go-tlsdialer: initial repository setup

[DerekBum]

To disable SSL by default we want to transfer OpenSSLDialer and any other SSL logic to the new go-tlsdialer repository.

go-tlsdialer serves as an interlayer between go-tarantool and go-openssl. All SSL logic from go-tarantool is moved to the go-tlsdialer.

go-tlsdialer still uses tarantool connection, but also types and methods from go-openssl. This way we are removing the direct go-openssl dependency from go-tarantool, without creating a tarantool dependency in go-openssl.

Moved all SSL code from go-tarantool, some test helpers. Added README.md, ci workflow.

Part of tarantool/go-tarantool#301

[DerekBum]

For the most part, code copied here will be deleted from the go-tarantool repo. However, there is the list of the parts, that will be in both repositories:

1. writeFlusher interface.
2. deadlineIO type and its methods.
3. parseAddress function.
4. Some of the test helpers in the ssl_test.go.

[oleg-jukovec]

Please, split the commit into commits:

• CI
• README
• Implementation

Let's also add:

• example_test.go file with a short example.
• CHANGELOG.md with a shot description of the changes.

You could although remove all ssl* prefixes at now.

[oleg-jukovec]

Thank you for the patch!

[DerekBum]

Fixed everything from the previous comments.

[DerekBum]

Updated the README, now it includes instructions about the application build (static and dynamic).