Stencil - Simple code templating for Go

Go doesn’t have user defined generics. While generics can be convenient, for much Go code, interfaces suffice. There are however, cases where the lack of generics leads to cumbersome code. The proposal below aims to handle a limited number of these cases using code generation. It builds on an idea proposed earlier in Gonerics. It does not propose a language change. Implementations will be command line tools.