Please clarify session resumption support 

Hello,

I couldn't find whether session resumption is supported. I see that the session cache is always disabled (https://github.com/lunarmodules/luasec/blob/master/src/context.c#L346), but session ticket support seems to be configurable (https://github.com/lunarmodules/luasec/blob/master/src/options.c#L128)