BUG: importing csv file when bottom right cell is empty

[drbenvincent]

I have tracked down an error I initially found in trying to use query.jl, but the root cause seems to be an apparent bug when importing csv files where the bottom right most cell is empty.

For example with the simple test csf file (attached test.csv) which looks like this

when you import the empty bottom right most cell is coming up as #undef rather than missing

This then causes all kinds of downstream havoc when doing anything with this cell. For example

EDIT: To clarify this error happens when the bottom right code cell in the csv file is empty. When it is explicitly coded as NA the import works fine