* Raft: Place locked items in create_items and fix get_pre_fill_items
`pre_fill` runs after item plando, and item plando could place an item
at a location where Raft was intending to place a locked item, which
would crash generation.
This patch moves the placement of these locked items earlier, into
`create_items`.
Setting items into `multiworld.raft_frequencyItemsPerPlayer` for each
player has been replaced with passing `frequencyItems` to the new
`place_frequencyItems` function.
`setLocationItem` and `setLocationItemFromRegion` have been moved into
the new `place_frequencyItems` function so that they can capture the
`frequencyItems` argument variable.
The `get_pre_fill_items` function could return a list of all previously
placed items across the entire multiworld which was not correct. It
should have returned the items in
`multiworld.raft_frequencyItemsPerPlayer[self.player]`. Now that these
items are placed in `create_items` instead of `pre_fill`,
`get_pre_fill_items` is no longer necessary and has been removed.
* self.multiworld.get_location -> self.get_location
Changed the occurences in the modified code.