[nginx-ingress-controller]: Add HTTPS default backend

[aledbf]

fixes #1331
fixes #1329

[bprashanth]

LGTM

[gambol99]

Post this merge i'm getting the following error, with SSL no longer working ...

2016/07/21 11:27:30 [error] 24#24: *224 no "ssl_certificate" is defined in server listening on SSL port while SSL handshaking, client: 10.10.4.1, server: 0.0.0.0:443
2016/07/21 11:27:30 [error] 24#24: *225 no "ssl_certificate" is defined in server listening on SSL port while SSL handshaking, client: 10.10.4.1, server: 0.0.0.0:443

I has to remove the section below to fix it

{{/* Check for default SSL backend */}}
 +    {{ if and (eq $server.Name "_") (not $server.SSL) -}}
 +    server {
 +        server_name {{ $server.Name }};
 +        listen 443;
 +        # return protocol error.
 +        return 444;
 +    }
 +    {{ end }}

[aledbf]

@gambol99 this issue was fixed in #1393.