Syntax and transpile support for continue statement

[TwitchBronBron]

Roku OS 11.5 introduced the continue statement. This PR adds the necessary parsing and transpiling to support using that feature as defined by Roku.

This does not address backwards-compatibile transpiling (i.e. transpile to labels and goto expressions). That effort is still ongoing in #489 and will be addressed at a future time.

[arturocuya]

Does the new Continue statement support plugin annotations?

[TwitchBronBron]

@arturocuya do you mean like this? If so, then no. I believe annotations are currently only applicable to the higher-level things like namespaces and functions.

while true 
    @YourCustomAnnotation
    continue while
end while

[arturocuya]

@TwitchBronBron Ah ok. I was asking because in another project I use brs for testing and it doesn't recognize newer statements like throw, so I exclude them from the compilation using an annotation:

    private sub validateArgs(args as object)
        if ((args.direction <> Direction.row) and (args.direction <> Direction.column))
            if (m.logger <> invalid)
                m.logger.error(ErrorCode.invalidDirection, args.direction)
            end if
            @deviceOnly
            throw ErrorCode.invalidDirection
        end if

[TwitchBronBron]

Oh, well if annotations work with throw, then they should also work for continue, as both are "statements".