Fixes for DB 5 to DB 4

Hi Sarah and Jess,

Made a couple small tweaks to db5to4.xsl here:

* Fixed a bug in the logic that was preventing xml:id and xml:lang from being converted properly to their DB 4 counterparts

* Expressly specifying preserve-space for all elements, just to ensure we're covered there.

Please go ahead and merge if these changes look OK to you.

Thanks,
Sanders