Support for multiple SRS Users

[ArthurAllshire]

I'm not sure if/how implementation of this is possible in terms of markup/filtering, but it would be nice if tagging SRS blocks for particular users would be possible (may be difficult, because you would need the ability to add multiple srs users on different schedules on the same card - however it may be possible to do in a not-too-cluttered way if implemented in the style of #138).

[Stvad]

One way of accomplishing this can be to allow users specifying additional tags that are attached the the cards alongside the metadata. So different people can specify their names as tags for example.
Allowing customization for "inline property" names (things like "interval") can be another approach