Enable hiding chromosomes of no interest for the compactness

[sehilyi]

In the following example of structural variants, ideally, we can remove chromosomes that do not contain any events (e.g., chr1).

We could support this by using custom assembly specification:

assembly: [
- ["chr1", 249250621],
  ["chr2", 243199373],
  ["chr3", 198022430],
  ["chr4", 191154276],
  ["chr5", 180915260],
  ["chr6", 171115067],
  ["chr7", 159138663],
  ["chr8", 146364022],
  ["chr9", 141213431],
  ["chr10", 135534747],
  ["chr11", 135006516],
  ["chr12", 133851895],
  ["chr13", 115169878],
  ["chr14", 107349540],
  ["chr15", 102531392],
  ["chr16", 90354753],
  ["chr17", 81195210],
  ["chr18", 78077248],
  ["chr19", 59128983],
  ["chr20", 63025520],
  ["chr21", 48129895],
  ["chr22", 51304566],
  ["chrX", 155270560],
  ["chrY", 59373566],
  ["chrM", 16571]
]

Relevant paper figure:

Reference: https://pubmed.ncbi.nlm.nih.gov/21215367/#&gid=article-figures&pid=figure-4-uid-4