Add to_fwf support

[cancan101]

Right now pandas can read fwf but there is no to_fwf.
From SO.

This output format seems similar to what numpy.savetxt handles.

[jreback]

see xref here: #3190

[koubaa]

Hello! Try using hollerith. pypi github. It's a (very) new python library that I developed that deals with fixed width formatting - and open to contribution. Unfortunately trying to use built-in python string formatting (or the C printf for that matter!) for fixed width doesn't work well for some widths when there are large integers and certain double precision floats.

[swarajban]

+1 on this feature request

[Tammura]

Anyone is working on this feature? I'm trying using to_string() method but it has no option to remove space between output columns