read_excel documentation does not mention names keyword
http://pandas.pydata.org/pandas-docs/stable/generated/pandas.read_excel.html
does not mention the keyword "names"

``` python
import pandas as pd
df = pd.read_excel('yourfile.xls', header=None, names=['Attribut', 'Value'])
```

is equivalent but simpler to

``` python
df = pd.read_excel(file, sheetname='Metadata', header=None)
df.columns = ['Attribut', 'Value']
```

names keyword is defined as in read_csv
names: List of column names to use as column names. To replace header existing in file, explicitly pass header=0.
