WIP: Optimization attribute added to the tableaux state

 * Only one ptimization in action: Semantc vs syntactic branching
First version of the reasoner API

Just a few major fanctions added
Adds a function to check for concept hierarchies

* Needs more testesting
WIP: There is a bug in model computation

It dows not terminate. It has something to do with the blocking
mechanisms, probably :(
WIP: This version seems to work well and efficiently

Now, I run all subsumption test from the beginning.
It seems non-optimized but it works much faster then the previous
solution, where I continued from the computed models
WIP: Added a new function to compute subsumptions

The new function tries to utilize the already expanded models
which are produced in the process of tbox consistency checking,
in order to test  concept subsumptions
Checks if a concept is subsumed by Bottom concept

i.e. cannot have any member
WIP: "Fast" method for individual classification does not work
Removed: Functions to compute classifications

The functions that computed individual classifications, and class
hierarchies, that re-used the already computed models from previous
consistency check. They were really slow or even non-terminating
WIP: Testing why algorithm does not perform well
Defined the main functions of the reasoner API
Some refactoring to Tableaux algorithm
Merged with semanticOpt
WIP: First step of backtracking completed

All LAssertions now are paired with a dependency set.
Currently d-set is not in use, but all functions/types refactored to
support them
WIP: Chaged returned value to Either to support failure

* [ModelsState] -> [Either ClashError ModelState]
WIP: Backtracking algorithm developed, but contains bug

* It does not work yet
WIP: Bug Fixed. Backtracking seems to work

* TODO: more testing
Bug fixed: ForAll clash d-set value updated
Replaced returned type of Tableaux to ModelState

Previously Tableaux returned ALL valid and in-valid models.
Now it only returns the first valid or the last clash if there is
no valid representation
Integrated the branch value to the tableaux state