Avoid exiting due to i-ADHoRe warnings

[Cecilia-Sensalari]

ksrates workflow for paralog Ks was interrupted if the following warning was raised by i-ADHoRe:

ERROR i-ADHoRe execution failed with standard error output:
Warning: Dubious indirect gene relationship between GENE1 and GENE2, closest genes get same color in alignment
ERROR Exiting.

This happened because the warning is handled as an error by i-ADHoRe (see issue #45 for more details) and consequently by ksrates too.

This merge request prints the warnings without interrupting the flow.