Fixed bug where TOPMODEL mode was broken due to the addition of
update_basin_patch_accumulator call to basin_daily_F in commit
cbaaac5672e64b7d71e00ca8c3f7ba5243801968. update_basin_patch_accumulator
assumes the existance of a basin route list of patches, which was only
being initialized when a flow table was present (i.e. in explicit
routing model).  Added construct_topmodel_patchlist, which creates a
dummy route list when in TOPMODEL mode.