Genome-wide association testing with haplotype data

[alimanfoo]

Umbrella issue to review and explore approaches to genome-wide association testing using haplotype data, i.e., haplotype association testing, specifically for discovery of insecticide resistance genes and variants. The goal being to propose some functions to implement in malariagen_data.

N.B., suggest scoping this issue to just use of haplotype data. See separate issues for association testing using SNP (#679) and CNV (#683) data.