patch 8.0.1149: libvterm colors differ from xterm

Problem:    libvterm colors differ from xterm.
Solution:   Use the xterm colors for libvterm.
diff --git a/Filelist b/Filelist
index 0587917..aaa6ba7 100644
--- a/Filelist
+++ b/Filelist
@@ -136,6 +136,7 @@
 		src/testdir/bench*.vim \
 		src/testdir/samples/*.txt \
 		src/testdir/if_ver*.vim \
+		src/testdir/xterm_ramp.vim \
 		src/proto.h \
 		src/proto/arabic.pro \
 		src/proto/blowfish.pro \