Fixing error in IfStatement parser

    * Modifying the repr for better comprehension.
    * TOFIX: By now the parser only parse one 'else if'.
Allowing the parser to generate AST nodes

    * Now the parser allows multiple statements inside if statements.
      (using ; for separating each statement)
Merge branch 'devel' of https://github.com/j3anc/SimpleJay into devel