`print stuff,` should avoid newline

In an IPython interpreter:

``` py
In [4]: print 1,
1

In [5]: print 1
1

In [6]: print 1,; print 2
1
2
```

In a regular Python interpreter:

``` py
>>> print 1,
1
>>> print 1
1
>>> print 1,;print 2
1 2
```
