Upgrade brick/money 0.5.3 to 0.7.0

[zgrguric]

Due to dependency conflicts with newer projects brick money should follow latest version.

Debug sample:

Problem 1
    - brick/money 0.5.3 requires brick/math ~0.7.3 || ~0.8.0 || ~0.9.0 -> found brick/math[0.7.3, ..., 0.9.3] but it conflicts with your root composer.json require (^0.10.2).
    - gndlf/xrpl_php dev-master requires brick/money ^0.5.3 -> satisfiable by brick/money[0.5.3].
    - Root composer.json requires gndlf/xrpl_php dev-master -> satisfiable by gndlf/xrpl_php[dev-master].

[AlexanderBuzz]

Ok, it is done!