Add missing blank line.


git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@4953 3789f03b-4d11-0410-bbf8-ca57d06f2519
diff --git a/BUILDING.txt b/BUILDING.txt
index f5ed717..65187b2 100644
--- a/BUILDING.txt
+++ b/BUILDING.txt
@@ -130,6 +130,7 @@
 5. When building TigerVNC, set the FLTK_FLUID_EXECUTABLE CMake variable to the
    location of the fluid executable that was built in Step 3 or installed in
    Step 4.  This gives CMake a hint as to where to find the FLTK library.
+
 6. If you did not install FLTK, then set the FLTK_INCLUDE_DIR CMake variable to
    the location of the FLTK source directory.