Update/improve Circos visualization

[jeffreybarrick]

Motivation: It is useful to visualize mutation comparisons in multiple ways, including on circular genome diagrams.

Implementation: Move this functionality out of C++ code in gdtools to make it more maintainable by the user community. Create a separate Python script/module for this purpose.

• Use existing (or improve) Python module for loading GenomeDiff files. Test these implementations: https://github.com/phageghost/gdparse, https://github.com/biosustain/genomediff-python
• Update current output to be compatible with current version of Circos (and clearly tie versions of this script to versions of Circos)
• Work on challenging cases: multiple reference sequences, many Genome Diff files.

[jeffreybarrick]

Here's an example of the current output that needs to be updated to work with the current version of Circos:

Ara-1_circos_input.zip

[kaiserlw]

I'm interested in working on this!

[jeffreybarrick]

Maybe we should use this javascript library instead: https://github.com/nicgirault/circosJS