Scope block semantics

[EltayebAhmed]

There are currently two entities that track the scope blocks. The

1. ScopeStack tracks scope blocks explicitly
   2.The LoopSwitchStack tracks scope blocks implicitly (each loop or switch is associated with a scope block)
   These two entities should be combined into a single class that
   A. Tracks scopes for use by variables
   B. Tracks the types of scope (if the scope is a function definition or switch or .......)

N.B. It might make sense to add this functionality to the already existing symbol table && symbol table builder

[EltayebAhmed]

The body of a loop does not necessarily have to be a scope block.. It could be a simple statement.
Maybe statement semantics are needed. Or maybe we could have different grammar namings for loop body statements

[EltayebAhmed]

Refs #18