Laws for PartialOrder and Order.
Laws for lattices including a partial order.

Will be used in another library for e.g. the lattice of subgroups defined by group intersection (meet)/union (join) , and the partial order "is subgroup of".
Laws for bounded (semi)lattices and partial order.
Added law for Monoid.isId.
Precised law structure for semigroup/monoid/group action.
Added a law for groups with a left and right action.
Merge pull request #325 from denisrosset/topic/group-laws

Topic/group laws