Fix for #4260

One can look into containers from the adjacent squares. Currently the list items command (V) will show them, but the look around command (X) will not. Anyway one can pick up the stuff from one square away so one has to be able to see it.

`map::sees_some_items` checks that the map has items, does not have the SEALED flag, does not have the CONTAINER flag (or the player is adjacent to the tile).
This function is used in tiles and curses build, as well as in live view, mouse over, look around.

This makes tiles and curses behave identical. Additionally one can see if the adjacent bed has items in it or not when just standing there (because the CONTAINER flag of the bed is ignored if adjacent).

Adds some checks for player being blind and therefor not able to see anything.

Fixes #4260

Fixes the bug from the last comment in #3412

> 5. Blood spatters are (almost)always displayed over items

Should already be fixed.