support noheader in immediate mode
make read_files handle file descriptors and commands
get rid of read_transpose
Use 'import mod', instead of 'from mod import ...'
move clean_output to reading instead of writing, so it works in raw mode
no longer strip the line before splitting it, in delim mode
use OFS in immediate mode
add sql option for arbitrary sql queries on files or command output
if there is an insert error, print the bad line