LibWasm: Implement most of the remaining instructions

This commit is a bit of a mixed bag, but most of the changes are
repetitive enough to just include in a single commit.
The following instructions remain unimplemented:
- br.table
- table.init
- table.get
- table.set
- table.copy
- table.size
- table.grow
- table.fill
- ref.null
- ref.func
- ref.is_null
- drop
- i32/i64.clz
- i32/i64.ctz
- i32/i64.popcnt
- i32/i64.rotl
- i32/i64.rotr
- X.trunc.Y
- X.trunc_sat.Y
- memory.size
- memory.grow
- memory.init
- memory.copy
- memory.fill
- elem.drop
- data.drop

Userland/Libraries/LibWasm/AbstractMachine/Interpreter.h

@@ -17,6 +17,8 @@ private:
     void interpret(Configuration&, InstructionPointer&, const Instruction&);
     void branch_to_label(Configuration&, LabelIndex);
     ReadonlyBytes load_from_memory(Configuration&, const Instruction&, size_t);
+    void store_to_memory(Configuration&, const Instruction&, ReadonlyBytes data);
+    void call_address(Configuration&, FunctionAddress);
 };
 
 }