Merge pull request #555 from LCSB-BioCore/mk-clear-unions

clean up some leftover unions with Nothing
6 jobs for develop in 7 minutes and 53 seconds (queued for 3 seconds)
Name Stage Failure
pages Documentation
 [7] notebook(inputfile::String, outputdir::String; config::Dict{Any, Any}, kwargs::Base.Pairs{Symbol, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})
@ Literate ~/.julia/packages/Literate/kB2Gm/src/Literate.jl:542
notebook(inputfile::String, outputdir::String)
@ Literate ~/.julia/packages/Literate/kB2Gm/src/Literate.jl:538
[9] top-level scope
@ /builds/lcsb-biocore/COBREXA.jl/docs/make.jl:27
in expression starting at /builds/lcsb-biocore/COBREXA.jl/docs/make.jl:19
Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1