Update TypedData in line with SNIP-12

lib/src/main/kotlin/com/swmansion/starknet/crypto/HashMethod.kt

@@ -0,0 +1,25 @@
+package com.swmansion.starknet.crypto
+
+import com.swmansion.starknet.data.types.Felt
+
+enum class HashMethod {
+    PEDERSEN {
+        override fun hash(first: Felt, second: Felt): Felt {
+            return StarknetCurve.pedersen(first, second)
+        }
+        override fun hash(values: List<Felt>): Felt {
+            return StarknetCurve.pedersenOnElements(values)
+        }
+    },
+    POSEIDON {
+        override fun hash(first: Felt, second: Felt): Felt {
+            return Poseidon.poseidonHash(first, second)
+        }
+        override fun hash(values: List<Felt>): Felt {
+            return Poseidon.poseidonHash(values)
+        }
+    }, ;
+
+    abstract fun hash(first: Felt, second: Felt): Felt
+    abstract fun hash(values: List<Felt>): Felt
+}