Bug: Reading from stream(io.Reader) two times

[djale1k]

With current implementation in Import Subscribers we are reading from the stream (io.Reader) two times, second read will be empty stream.

1. CheckLines with limit func
2. The actual read in import svc.

[FilipNikolovski]

We can create a new reader from the same bytes and pass it along. Here's an example: https://siongui.github.io/2018/10/28/go-read-twice-from-same-io-reader/