ExcelFile throws an exception if parsing a file with only two lines
Example (paste this in an Excel file):

Test    Test1
aaaa   bbbbb

``` python
excel_data = pandas.ExcelFile("test.xls")
parsed = pandas.parse("Sheet1")

/usr/lib64/python2.7/site-packages/pandas/io/parsers.pyc in parse(self, sheetname, header, skiprows, index_col, parse_dates, date_parser, na_values, chunksize)
    629                                    parse_dates=parse_dates,
    630                                    date_parser=date_parser,
--> 631                                    na_values=na_values, chunksize=chunksize)
    632 
    633     def _parse_xlsx(self, sheetname, header=0, skiprows=None, index_col=None,

/usr/lib64/python2.7/site-packages/pandas/io/parsers.pyc in _parse_xls(self, sheetname, header, skiprows, index_col, parse_dates, date_parser, na_values, chunksize)
    684                             date_parser=date_parser,
    685                             skiprows=skiprows,
--> 686                             chunksize=chunksize)
    687 
    688         return parser.get_chunk()

/usr/lib64/python2.7/site-packages/pandas/io/parsers.pyc in __init__(self, f, delimiter, names, header, index_col, na_values, parse_dates, date_parser, chunksize, skiprows, skip_footer, converters, verbose, encoding)
    262             self.data = f
    263         self.columns = self._infer_columns()
--> 264         self.index_name = self._get_index_name()
    265         self._first_chunk = True                                                                                                                                                                                                           
    266                                                                                                                                                                                                                                            

/usr/lib64/python2.7/site-packages/pandas/io/parsers.pyc in _get_index_name(self)                                                                                                                  
    381                                                                                                                                                                                                                                            
    382         try:                                                                                                                                                                                                                               
--> 383             next_line = self._next_line()                                                                                                                                                                                                  
    384         except StopIteration:                                                                                                                                                                                                              
    385             next_line = None                                                                                                                                                                                                               

/usr/lib64/python2.7/site-packages/pandas/io/parsers.pyc in _next_line(self)                                                                                                                       
    351                 self.pos += 1
    352 
--> 353             line = self.data[self.pos]
    354         else:
    355             while self.pos in self.skiprows:

IndexError: list index out of range
```

Works correctly if the number of lines is at least 3.  Pandas is from yesterday's git (path names have been slightly trimmed to improve readability).
