importDefault allows getSymbol functions to be called via namespace, …

[woodvi]

…eg quantmod::getSymbols (instead of getSymbols)

[joshuaulrich]

Thanks for the report and the patch, but I decided to use what I think is a more robust solution. I did not like the assumption that the output from sys.call() would either be a length-1 vector (so rev() wouldn't alter it), or that "getSymbols" would be at the end of the vector.