Adjusted poetry indentation for Drum-Taps

Line breaks in the Drum-Taps poems were not displaying with an indent, as they did in the original volume.  I have changed the stylesheet so that line break indents are now displaying.  This also affects the display of poetry in Drum-Taps and Sequel to Drum-Taps and Complete Prose Works.

Thanks to Adam Bradford for noting this issue. 

~ Nikki