Group parameters by component

Today hub supports following notation (see below) that only allow to group parameters prefixed by another parameter. Yet we are getting more and more parameters that are rather generic.

```yaml
parameters:
- name: kubernetes
component: foo
parameters:
- name: namespace
value: kube-system
# ...
- name: ingress
component: foo
parameters:
- name: hosts
value: foo.example.com
# ...
```

Proposed form brings more compact form of the same

```yaml
parameters:
- component: foo
parameters:
- name: kubernetes.namespace
value: foo
- name: ingres.hosts
value: foo.example.com
- component: bar
parameters:
- name: kubernetes.namespace
value: bar
- name: ingres.hosts
value: bar.example.com
```