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 ;-)
disagree.... I think it's useful to know "this struct fulfils the contract of X interface, so i can pass it around as one" given that Go doesn't otherwise help you understand what contract a struct fulfils.  I don't want to have to read all the methods assigned to the struct in order to conclude "oh!  this is a Foo!".  

A comment at the top explicitly saying "this Bar is a Foo" seems very useful.