Polymake.jl 0.9.1 released

Today Polymake.jl 0.9.1 has been released.

Diff since v0.9.0

Closed issues:

• check if we can / should (temporarily) adjust PERL5LIB while loading (#424)
• IJulia in a multi user environment trying to write in global kernel resource_dir (#430)

Merged pull requests:

• Update OSCAR URL (#422) (@fingolfin)
• allow Mongoc.jl 0.9 (#423) (@benlorenz)
• init: ignore PERL5LIB during init (#425) (@benlorenz)
• CI: remove julia 1.7 (#429) (@benlorenz)
• [IJulia] improve threejs installation for jupyter (#431) (@benlorenz)
• Use Documenter 0.27.x (#432) (@fingolfin)
• Don’t throw an error if jupyter kernelspec does not exist (#433) (@joschmitt)
• Change an @info during precompilation to @debug (#434) (@fingolfin)
• Move test dependencies to test/Project.toml (#435) (@lgoettgens)
• CI: enable color for OscarCI diffs (#436) (@fingolfin)
• Add Aqua.jl for some static testing (#437) (@lgoettgens)
• oscarci: remove ‘if’ for doctest after OscarDevTools 0.2.11 (#438) (@benlorenz)