Adds missing hostname to ssl handle

[SinisterRectus]

#212
luvit/luvit#986
luvit/luvit#987

[creationix]

Looks great. My only suggestion is to have .isServer for the boolean flag instead of just .server. It confused me for a bit thinking it held some table or uv struct.

[SinisterRectus]

It was originally server, but it makes more sense as isServer. I made the change. As for setting the hostname, I'm assuming that it's been done right. Nothing broke on my end, so that's a plus.

[SinisterRectus]

I implemented this fix thinking that I was not touching any part of the public API; however, it seems that this PR would make secure-socket incompatible with older versions of coro-net. In other words, you would need to update to the latest coro-net to use the latest secure-socket. We'll have to carefully select version numbers this time, or I can adjust the fix to something non-breaking; something more like that which is proposed in #212.

[creationix]

We should probably just bump the major version on coro-net and secure-socket to be safe.

Looks good!

[creationix]

I'm also fine with the suggestion in #212, it's a less invasive change and should work as well right?

[SinisterRectus]

As discussed in IRC, I've restored backwards compatibility. Note that servername should technically be hostname, not host. Luckily, coro-http passes hostname to coro-net as host. This would only be a problem if anyone is using coro-net directly, and if they pass it an options table where host is not the same as hostname. We could add a fix for this with ssl:set('hostname', servername:match("^([^:/]+)")), but it seems like an edge case.