lab 1 task C first commit

Task_C/src/interpreter/lisp/Add.java

Task_C/src/interpreter/lisp/CaseConditional.java

Task_C/src/interpreter/lisp/CompoundExpression.java

Task_C/src/interpreter/lisp/Context.java

Task_C/src/interpreter/lisp/InterpreterTest.java

Task_C/src/visitor/Minus.java