ENH/API: check for full rows of DataFrame with isin?
Seeing this SO question: http://stackoverflow.com/questions/23896088/dropping-rows-in-dataframe-if-found-in-another-one/, I was wondering if this is something that could be provided as functionality to the `.isin()` method.

The problem at the moment to use `isin` to check for the occurence of a full row in a DataFrame is that a) `isin` checks for the values in each column seperately, indepenently of the values in other columns (so you cannot check if the values occur together in the same row) and b) `isin` also checks if the index label matches.

Or are there better ways to check for the occurence of a full row in a DataFrame?
