Test-suite coverage for type-class laws of core types

[recursion-ninja]

This PR adds QuickCheck-based property tests for the type-class laws of all data-types exported from the Database.LSMtree module. This PR is motivated by the code coverage discussion from #662. Many of the data-types have non-trivial instances of type-classes and it is prudent to provide assurance that the data-types have lawful instance.

Note: Exception data-types were excluded from coverage as they tend to only have a Show instance.

Here is the coverage improvement of the most impacted modules.

Added	Old	New	Module
47	47%	82%	Database.LSMTree
29	40%	70%	Database.LSMTree.Internal.Config
4	35%	37%	Database.LSMTree.Internal.Paths
3	37%	75%	Database.LSMTree.Internal.Range
7	20%	23%	Database.LSMTree.Internal.Snapshot
15	48%	54%	Database.LSMTree.Internal.Unsafe
…	…	…	More modules
110	42%	45%	Total