LuaLDAP v1.2.3-1 open_simple() doesn't allow a space-separated list of hosts

Hi,

Not sure where to put this bug report, but the LuaLDAP from [1] GitHub is throwing an error when you call open_simple() with a space-separated 'hostname'.

Working Example:

```

local ldap = require( "lualdap" )

local ld = assert( ldap.open_simple( "ldap1.server.com", "username", "password" ) )

```

Response: ""

Broken Example:

```

local ldap = require( "lualdap" )

local ld = assert( ldap.open_simple( "ldap1.server.com ldap2.server.com ldap3.server.com", "username", "password" ) )

```

Response: "LuaLDAP: Error connecting to server"

In LuaLDAP v1.1.1 it works just fine. Any ideas?

Regards,
Ryan

[1] https://github.com/bdellegrazie/lualdap