harm: `Make*`-traits should describe arguments only

[monoid]

Many instructions have very similar structure of possible arguments (for example, ldr and str). Right now they define MakeLdr/Ldr<...> and MakeStr/Str<...> with macros and ldr/str functions.

Instead, we should define with macros common trait and type MakeLdrLikeArgs/LdrLikeArgs<...>, and define

pub struct<D, A> Ldr(LdrLikeArgs<D,A>);

pub fn ldr<D, A, RD, RA>(dst: D, addr: A) -> Ldr<RD, RA>
    where LdrLikeArgs<RD, RA>: MakeLdrLikeArgs<D, A>
{
    Ldr(LdrLikeArgs::make(dst, addr))
    // or, perhaps, LdrLikeArgs::make(dst, addr, Ldr) to work with both fallible and unfallible variants
}

Failing variants of Make*-traits should be handled, though.

It should make the codebase smaller and reduce compilation time.

[monoid]

The suggested approach was used for movewide.rs in #36, but it seems to make types little verbose.

[monoid]

The approach works, but refactoring loads and stores to use it is not of high priority. Leaving the issue open though.