abyss 2.0.2
abyss 2.0.2

Fix compile errors with gcc-6 and boost-1.62.
Increase default value of maxk to 128.
sqlite is no longer a dependency.

Closes #4506.

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

dpo/homebrew-science,parcollet/homebrew-science,DabeDotCom/homebrew-science,heuermh/homebrew-science,kozo2/homebrew-science,philippbayer/homebrew-science,maplesond/homebrew-science,quantumsteve/homebrew-science,pditommaso/homebrew-science,andrewjpage/homebrew-science