add support for `proteus:",(protobuf field id)"` in golang tag

[liasece]

Now you can specify the ID of the peoto file in the following way:

type Example struct {
    Filed int32 \`proteus:",101"\`
}

This example will generate the following protobuf message.

message Example {
        int32 Filed = 101;
}

[dennwc]

Please rebase on the latest master - it should fix the CI.

[liasece]

Add tests and example