[v1] - custom component types

[michalak111]

I want to make it possible for users to create custom template and then generate it with selecting declared templates with --t <template>

So user can declare their own template like container, and then generate it in this way:

rctgen --n Home --t container

TODO

• update doc
• finish todos
• improve custom config (?)
• possibility of adding custom files like types.ts for Typescript users