BUG: pd.read_excel error when a cell contains string "INF"
Here is how to reproduce the bug: run this script:

    import pandas as pd
    pd.read_excel('test.xlsx')
    # idem with pd.read_excel('test.xlsx', engine='openpyxl')
    # so it's not specific to xlrd or openpyxl

with this [test.xlsx](https://gget.it/tuha/test.xlsx) file:

a | b
-- | --
12 | 1
14 | 1
15 | 1
16 | INF

Error:

> OverflowError: cannot convert float infinity to integer

Why does this happen / why is there a integer conversion? No automatic integer parsing has been asked.

___

PS: Congrats for this great project!