Chore: Extract base template in it's own file, inject values with Tera

[benlubas]

Instead of https://github.com/NTBBloodbath/norgolith/blob/master/src/cmd/init.rs#L61-L85

We could instead write the template in it's own template file, load it with Tera, and use normal blocks to fill the values that are currently inserted by rust. This would provide more configurability, and would help code quality as the base template grows