TemplateConfig implementation with Kubernetes

Initial implementation of TemplateConfig REST endpoint.

See the project.json example.

To test this PR:

```
$ curl -d @pkg/template/examples/project.json \
  http://localhost:8080/api/v1beta1/templateConfigs
```

This will return `Config{}` which is essentially the same as a `templateConfig{}` but without parameters.

**FYI**: This is a wip, all commits will be squashed in the end. @VojtechVitek is working on validation atm. so I don't want to force push ;-)
```
git grep 'errs "github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"'
Godeps/_workspace/src/github.com/GoogleCloudPlatform/kubernetes/pkg/api/validation/validation.go:       errs "github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
Godeps/_workspace/src/github.com/GoogleCloudPlatform/kubernetes/pkg/apiserver/apiserver_test.go:        apierrs "github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
Godeps/_workspace/src/github.com/GoogleCloudPlatform/kubernetes/pkg/kubelet/config/config.go:   apierrs "github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
Godeps/_workspace/src/github.com/GoogleCloudPlatform/kubernetes/pkg/kubelet/validation.go:      apierrs "github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
pkg/build/api/validation/validation.go: errs "github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
pkg/template/api/validation/validation.go:      errs "github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
```
Seems like there's a precedent to call it `errs` :/