Fix subtle problem with redirection in nt/configure.bat.

Fix subtle problem with redirection in nt/configure.bat.

 nt/configure.bat (genmakefiles): Move the redirection away from the
 end of the command, to avoid excess whitespace at the end of Make
 variables created at configure time, and also avoid things like
 "FOO1>>config.settings", where "1" gets interpreted as the file
 descriptor and eaten up.  This fixes breakage introduced by the
 last change, without reintroducing the bug fixed by that change.