Remove a number of now-unused InstallPlan operations
Remove a number of now-unused InstallPlan operations

These were the primitives used by executeInstallPlan to change the
package states to Processing, Installed, Failed etc.

The 'ready' is still used in a couple other places, so those need to be
modified before the old 'ready' can be removed.

themoritz/cabal,themoritz/cabal,sopvop/cabal,mydaum/cabal,mydaum/cabal,sopvop/cabal,sopvop/cabal,themoritz/cabal