Enable easier importing of quiver subpackage

[Tracking bug 22690]

[git-p4: depot-paths = "//depot/software/bioinformatics/tools/GenomicConsensus/": change = 123498]
Remove old demo

[Tracking bug 22690]

[git-p4: depot-paths = "//depot/software/bioinformatics/tools/GenomicConsensus/": change = 123499]
Move QuiverConfig into model module

[Tracking bug 22690]

[git-p4: depot-paths = "//depot/software/bioinformatics/tools/GenomicConsensus/": change = 123500]