[board, core, moves, position] Implement castling

Implement a new method on Position that evaluates whether the active color can castle
on a given wing of the board. Then, implement making a castling move in the position.

Make a new Wing enum in the core crate to specify kingside or queenside. Replace the
Castle enum from the board crate with this one. This caused a lot of churn...

Along the way fix a bunch of tests.

Note: there's still no way to actually make a castling move in explorer.

board/src/castle.rs

@@ -3,22 +3,5 @@
 mod parameters;
 mod rights;
 
+pub use parameters::Parameters;
 pub use rights::Rights;
-
-use chessfriend_core::Color;
-use parameters::Parameters;
-
-#[repr(u8)]
-#[derive(Copy, Clone, Debug, Eq, PartialEq)]
-pub enum Castle {
-    KingSide = 0,
-    QueenSide = 1,
-}
-
-impl Castle {
-    pub const ALL: [Castle; 2] = [Castle::KingSide, Castle::QueenSide];
-
-    pub fn parameters(self, color: Color) -> &'static Parameters {
-        &Parameters::BY_COLOR[color as usize][self as usize]
-    }
-}