Refactored into separate files

Remote Execute to EvalString
Fix error messages in Eval
Fix quote tests
Refactoring to properly handle proc calling etc

Split Eval into Eval and the recursive evalValue. Eval just loops over
the values and evaluates them with evalValue. This also makes calls
expressions like "(1)" illegal and returns the last value in expression
like "1 2 3".
Refactored proc running into private method
Change Proc string and error message
Make Proc variables private