Disable SSL by default

[oleggator]

Disable SSL support by default (replace go_tarantool_ssl_disable tag with go_tarantool_ssl_enable).
SSL is used in less than 50% cases, but it breaks cross-compilation due to the use of cgo.

[DifferentialOrange]

It was a product decision, not an accidental one. @NeraverinTarantool may provide more info

[Mons]

Why at all is used go-openssl instead of crypto/tls?

[oleg-jukovec]

The idea was to provide a fully compatible solution.

For example, crypto/tls does not support DHE ciphers, but Tarantool Enterprise does it + the "official" GOST engine could be used instead of third-party implementations on Go.