Bug in min_coverage filter

[tleonardi]

If a ref_id is completely missing from one of the eventalign files it is not filtered out by the Whitelisting function as it should be.

This is due to the fact that the cond_lab and and sample_lab for the missing condition are not present in ref_dict, and therefore the assertion error is never raised.

nanocompore/nanocompore/Whitelist.py

Lines 242 to 246 in 9f8effe

	for cond_lab, cond_dict in ref_dict.items():
	valid_dict[cond_lab] = OrderedDict()
	for sample_lab, read_list in cond_dict.items():
	# Filter out if coverage too low
	assert len(read_list) >= min_coverage