mans doesn't work on Solaris

trying a simple client test on Solaris:

```
/var/tmp/mdns_client
2015/05/27 23:49:54 [ERR] mdns: Failed to bind to udp4 port: listen udp4 0.0.0.0:5353->224.0.0.251: option not supported by protocol
2015/05/27 23:49:54 [ERR] mdns: Failed to bind to udp6 port: listen udp6 [::]:5353->ff02::fb: option not supported by protocol
```

Code:

``` go
package main

import (
"fmt"
"github.com/hashicorp/mdns"
)

func main() {
// Make a channel for results and start listening
entriesCh := make(chan *mdns.ServiceEntry, 4)
go func() {
for entry := range entriesCh {
fmt.Printf("Got new entry: %v\n", entry)
}
}()

// Start the lookup
mdns.Lookup("_http._tcp", entriesCh)
close(entriesCh)
}

```

Running go test in mans produces:

```
$ go test -v
=== RUN TestServer_StartStop
--- FAIL: TestServer_StartStop (0.00s)
server_test.go:12: err: No multicast listeners could be started
=== RUN TestServer_Lookup
--- FAIL: TestServer_Lookup (0.00s)
server_test.go:20: err: No multicast listeners could be started
=== RUN TestNewMDNSService_BadParams
--- PASS: TestNewMDNSService_BadParams (0.00s)
=== RUN TestMDNSService_BadAddr
--- PASS: TestMDNSService_BadAddr (0.00s)
=== RUN TestMDNSService_ServiceAddr
--- PASS: TestMDNSService_ServiceAddr (0.00s)
=== RUN TestMDNSService_InstanceAddr_ANY
--- PASS: TestMDNSService_InstanceAddr_ANY (0.00s)
=== RUN TestMDNSService_InstanceAddr_SRV
--- PASS: TestMDNSService_InstanceAddr_SRV (0.00s)
=== RUN TestMDNSService_InstanceAddr_A
--- PASS: TestMDNSService_InstanceAddr_A (0.00s)
=== RUN TestMDNSService_InstanceAddr_AAAA
--- PASS: TestMDNSService_InstanceAddr_AAAA (0.00s)
=== RUN TestMDNSService_InstanceAddr_TXT
--- PASS: TestMDNSService_InstanceAddr_TXT (0.00s)
=== RUN TestMDNSService_HostNameQuery
--- PASS: TestMDNSService_HostNameQuery (0.00s)
=== RUN TestMDNSService_serviceEnum_PTR
--- PASS: TestMDNSService_serviceEnum_PTR (0.00s)
FAIL
exit status 1
FAIL github.com/hashicorp/mdns 0.013s
```