Recheck TANDEM:DUPs

[Irallia]

Our results from the mini example are giving us:

#CHROM	POS	ID	REF	ALT	QUAL	FILTER	INFO	FORMAT	MYSAMPLE
chr1	110	.	N	<DUP:TANDEM>	1	PASS	END=125;SVLEN=16;iGenVar_SVLEN=4;SVTYPE=DUP	GT	./.
chr1	181	.	N	<DUP:TANDEM>	1	PASS	END=188;SVLEN=8;iGenVar_SVLEN=7;SVTYPE=DUP	GT	./.
chr1	181	.	N	<DUP:TANDEM>	2	PASS	END=188;SVLEN=8;iGenVar_SVLEN=8;SVTYPE=DUP	GT	./.
chr1	509	.	N	<DUP:TANDEM>	1	PASS	END=529;SVLEN=21;iGenVar_SVLEN=9;SVTYPE=DUP	GT	./.

The real duplications are:
...GGG ATATATTT ATATATTT TAC... <- Tandem Duplication ref: (180, 188] tandem duplicated
...GCG TAACCCGGG TAACCCGGG TAACCCGGG TAACCCGGG TAACCCGGG TAC... Duplication in reference and read covered by SA tag ref: (509, 527] with copynumber=5

Jörg also raised the question why we calculate the sv length as difference +2. Originally posted by @joergi-w in #223 (comment)