wiggletools: revision for gsl
wiggletools: revision for gsl

Closes #5864.

Signed-off-by: Shaun Jackman <b580dab3251a9622aba3803114310c23fdb42900@gmail.com>

heuermh/homebrew-science,pditommaso/homebrew-science,dpo/homebrew-science,quantumsteve/homebrew-science,andrewjpage/homebrew-science