Scalars don't propagate in DataFrame constructor
This only works if an index is specified; fails in the index inference process

```
In [1]: DataFrame({'a' : randn(10), 'b' : 6})
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
/home/wesm/code/pandas/<ipython-input-1-16dbfdf3cea7> in <module>()
----> 1 DataFrame({'a' : randn(10), 'b' : 6})

/home/wesm/code/pandas/pandas/core/frame.pyc in __init__(self, data, index, columns, dtype, copy)
    367             mgr = self._init_mgr(data, index, columns, dtype=dtype, copy=copy)
    368         elif isinstance(data, dict):
--> 369             mgr = self._init_dict(data, index, columns, dtype=dtype)
    370         elif isinstance(data, ma.MaskedArray):
    371             mask = ma.getmaskarray(data)

/home/wesm/code/pandas/pandas/core/frame.pyc in _init_dict(self, data, index, columns, dtype)
    446         # figure out the index, if necessary
    447         if index is None:
--> 448             index = extract_index(data)
    449         else:
    450             index = _ensure_index(index)

/home/wesm/code/pandas/pandas/core/frame.pyc in extract_index(data)
   4540             else:
   4541                 have_raw_arrays = True
-> 4542                 raw_lengths.append(len(v))
   4543 
   4544         if have_series or have_dicts:

TypeError: object of type 'int' has no len()
```
