Enable support for non seekable resources (such as a http response). Does not stream atm
Test for streamed csv, xls and xlsx
Enable stream support in all table sets
use assert_equal
proper test requirements file
pass encoding for from_fileob, raise exception if encoding could not be determined
Proper non blocking, buffered stream, finally fixes #24
Merge pull request #27 from okfn/24-http-files

Enable support for non seekable resources - fixes #24.
Merge branch '25-more-csv-arguments'

Conflicts:
	messytables/commas.py