Doesn't detect conserved reads if the path contains the string "_mirbase"

[netbofia]

This occurs with some frequency if people test different databases for conserved reads.
They tend to call the project xxx_mirbase this them interferes down downstream with a regular expression that is way to greedy and does a replace string in the wrong place of the path.

Detected in "scripts/filter_genome_mirbase.sh" check it occurs in others, but I expect it to be contained to this script.