Removed PLY warnings from Hello World compiler

That way user doesn't have to be bothered by warning messages. Can be easily turned off by removing "errorlog=...NullLogger()" in svelCompile.py where ... is either lex or yacc.

Left PLY warnings in main lib for now.
Hello World testing a main function

Syntax isn't correct and everything's pretty janky, but here's the deal:

printhelloworld.py just prints "Hello, World!"

test-helloworldMain.py compiles code that runs printhelloworld.py and compares output for correctness.

That creates a file called test.py.

To test things out:
```
python test-helloworldMain.py
python test.py
```

You should see ```Hello World passed.```
Merge pull request #7 from kaitlinhuben/master

Hello World testing main function & removed PLY warnings from Hello World compiler
added svelTraverse to lib; renamed old svelTraverse in helloworld to avoid conflicts
svelTraverse.py to lib
moved files around; todo: update lib/svelTraverse.py to actual grammar
added traverse methods to handle hello, world example
fixed output .py format
Merge pull request #8 from chrso/master

added svelTraverse to lib; renamed old svelTraverse in helloworld to avo...
Merge pull request #9 from emilyhsia/master

Python methods to create, compile, and run Svel Java file to test/assert against inputs and outputs
Python Funct class representing svel's funct

contains the assert method (called _assert())

assert() : creates new Svel Java file with extracted
method to test, compiles the file, and runs it to test
the given the input and output

(refactored old jextractor.py methods, deleted jextractor)