Merge branch 'release/0.3' into develop
Fixed up the variant configuration

The variants in the configuration now only ensure that setup.X has a
value rather than overwritting any that might be in the configuration.
Fix another problem with variants

Only some of the variant names correspond to schroot script options.
Check to see if the setup file exists before adding it to the schroot
options.
Merge branch 'release/0.3.2'