Update TIdSSLIOHandlerSocketOpenSSL to enable TLS 1.1 and 1.2 by default

[rlebeau]

TIdSSLIOHandlerSocketOpenSSL currently enables only TLS 1.0 by default, but public servers are slowly moving away from TLS 1.0 and now requiring TLS 1.1 and higher, so the SSLOptions.SSLVersions property should be updated to enable TLS 1.1 and 1.2 by default.

FYI, many servers, like Office 365, are even starting to drop support for TLS 1.1 and now require TLS 1.2 or higher only.

Also, read up about the BEAST attack against TLS 1.0.