ValueFnIter_Case1_FHorz: internal reorg

Most users can ignore this, is only for the info of those who look under the hood. Later today I will push a big reorg of ValueFnIter_Case1_FHorz. It has been internally rebuilt around a new hierarchy to make it easier to keep track of all the different preference and endogenous state combinations. Namely

ValueFnIter_Case1_FHorz        level 1
└─ preference dispatcher       level 2   read this preference's parameters once
   └─ endogenous state type    level 3
      └─ semiz                 level 4
         └─ solver (DC / GI)   level 5
            └─ raws

I have been doing heaps of work implementing all the various combinations of endogenous state types and exogenous shock types. Now I am working on doing all of this various preference types. It was becoming a mess and this reorganizing it into a nice clean hierarchy.