Add a new tool holding Xvfb bits.

xvfb/COPYING/xcb-proto-1.6.txt

+Copyright (C) 2001-2006 Bart Massey, Jamey Sharp, and Josh Triplett.
+All Rights Reserved.
+
+Permission is hereby granted, free of charge, to any person
+obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall
+be included in all copies or substantial portions of the
+Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS
+BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
+
+Except as contained in this notice, the names of the authors
+or their institutions shall not be used in advertising or
+otherwise to promote the sale, use or other dealings in this
+Software without prior written authorization from the
+authors.