Give the ability to export encode and decode methods in a separate way

[Frabat]

Hi!
Currently I'm working on a project where we're using TS-proto to generate interfaces from protobuf files.
We are also using the encode methods generated by ts-proto to serialize binary messages.
Since we don't really need decode methods, and since those take up a lot of space, could be reasonable to insert a flag to generate only the encode (or decode) methods instead of both?

I've already did an edit for this, if this feature makes sense to you I could open a PR.

[stephenh]

Hi @Frabat ; sure if you wanted to modify the existing outputEncodeMethods to support values like:

outputEncodeMethods = true | false | "encode-only" | "decode-only"

I think that'd be fine. Thanks!

[Frabat]

Ok awesome! I'll finish and open a pull request

[akornatskyy]

consider to look at this from the client vs server standpoint, e.g. in case of client I am interested in encode for request but decode for response... for the server it is the other way around.