Fix problem with BAM username

[JosePizarro3]

When multiple strings are repeated in username (example, "Markus Mueller" and "Matthias Mueller" are both "mmueller"), then BAM assigns a digit to the second case.

This is a very human-involved problem, and I would like to standardize the way of handling this with code, not with human intervention, so that parsers and automated scripts can properly obtain this and we can give interoperable tools to our users (even outside of the scope of the Data Store).

@jraedler @carlosmada22