[DX] Lead Ammit to be dependency free - Scalar II

[gmorel]

Rebund of https://github.com/imediafrance/ammit/issues/38

TODO

• [x] Validate Float without beberlei/assert
  • Refactor Pure\FloatValidatorTrait
• [x] Validate Int without beberlei/assert
  • Refactor Pure\trait IntegerValidatorTrait
• [x] Validate String without beberlei/assert
  • Refactor Pure\StringValidatorTrait