Fix improvePlan so the index is updated incrementally It's important since later packages can depend on earlier ones having been changed from configured to pre-existing. That is afterall the whole point of considering them in reverse toplogical order. Also, remove duplicates in the dependencies list of installed packages since ghc-pkg does not currently prevent duplicates in (eg multiple depends on the same version of base). See ghc bug #2230.
Fix improvePlan so the index is updated incrementally
It's important since later packages can depend on earlier ones having
been changed from configured to pre-existing. That is afterall the
whole point of considering them in reverse toplogical order.
Also, remove duplicates in the dependencies list of installed
packages since ghc-pkg does not currently prevent duplicates in (eg
multiple depends on the same version of base). See ghc bug #2230.


IreneKnapp/Faction,IreneKnapp/Faction