zclwrite: TokenGen interface has EachToken, not AppendToTokens
zclwrite: TokenGen interface has EachToken, not AppendToTokens

Although building a flat array of tokens is _one_ use-case for TokenGen,
this new approach means we can also use the interface to write to an
io.Writer without needing to produce an intermediate buffer.

hashicorp/hcl,strivecast/hcl,strivecast/hcl,zclconf/go-zcl,hashicorp/hcl,strivecast/hcl,zclconf/go-zcl,strivecast/hcl,hashicorp/hcl,hashicorp/hcl,zclconf/go-zcl,hashicorp/hcl,strivecast/hcl