Fuzz test by using properties

[amsorrytola]

used fundamental properties to test addz,subz,mulz
for example in addition is associative,commutiative.

[amsorrytola]

For
Addz functions tests if it's commutative,associative and if there exists a additive inverse and additive identity

For subz
It should be non commutative, non associative

For mulz
It should be
Non commutative, associative, distributive and multiplicative inverse should exist

[0xpanicError]

LGTM