- SearchVisitor now recognizes function declaration and other upgrades was made too.

- Minor fix in recognizing variables in FindVariableVisitor.
- Added FindVisitor as common ancestor for all finding visitors specialized to find variables, functions etc.
- Expression type renamed to ElementType.
- Added search type to indicate what type of element type we are searching for (global variable, local variable, function etc...)
- Added simple test for renaming global variables.
- Added test for global variable renaming.
- Fixed bug in ContextVisitor where it adds inception if theres two functions in line.