There are two places where the segmentation can fail with UNSEG_ONLY_V/J.
The first one, when there is no segmentation point, previously returned UNSEG_ONLY_V/J
even when there was only one (possibly noisy) V/J k-mer.

This is now corrected, UNSEG_ONLY_V/J is triggered only when one has at least DETECT_THRESHOLD k-mers (now 5).
Ideally, we should use here an e-value check, but the segmentation point returned by kaa->getMaximum()
is not really meaningfull in these cases and my lead to false statistics computations.