Comparative analysis flow


## Initial specs for comparative analysis

Initially we will only allow pairwise comparisons. So only two genomes can be selected at a time. The flow is like this:

A user does this:

1). Choose two genome assemblies
2). Click "compare"
3). This get you to a Galaxy workflow for pairwise comparison https://vgp.usegalaxy.org/u/cartman/w/imported-align-chain-and-net
4). Get resulting MAF
5). Display MAF at UCSC
6). Process MAF using UCSC MAFTools

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To do:

1). Ensure that results of workflow comply with UCSC data (e.g., can we replicate UCSC data https://github.com/galaxyproject/alignment-pipeline/issues/1)
2). Wrap all UCSC MAF Tools
3). Refine https://github.com/galaxyproject/kc-align