Fix wasm.simd tests

Make sure text syntax can be assembled by current WABT (revision
048e01a).

Use `v128` as vector value type. Fix names, modifiers, and indices for
instructions working with lanes. Get rid of build instruction, switch to
literal arguments for some of the intstuctions ("shuffle").

Add alignment to store instructions, to match binary code in `.wasm`
files.

Remove boolean SIMD tests -- boolean operations are deprecated.

Don't enable f32x4 test, it hits a bug in the engine.

Test binaryArithmeticTests would be handled in a separate commit.

Author: penzn