Doing some cleanup.

third_party/docbook-xsl-1.78.0/params/column.gap.back.xml

Index: third_party/docbook-xsl-1.78.0/params/column.gap.back.xml
diff --git a/third_party/docbook-xsl-1.78.0/params/column.gap.back.xml b/third_party/docbook-xsl-1.78.0/params/column.gap.back.xml
deleted file mode 100644
index 3aaa1d3f11821462d965547c391e3b9d96a7762c..0000000000000000000000000000000000000000
--- a/third_party/docbook-xsl-1.78.0/params/column.gap.back.xml
+++ /dev/null
@@ -1,28 +0,0 @@
-<refentry xmlns="http://docbook.org/ns/docbook"
-          xmlns:xlink="http://www.w3.org/1999/xlink"
-          xmlns:xi="http://www.w3.org/2001/XInclude"
-          xmlns:src="http://nwalsh.com/xmlns/litprog/fragment"
-          xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
-          version="5.0" xml:id="column.gap.back">
-<refmeta>
-<refentrytitle>column.gap.back</refentrytitle>
-<refmiscinfo class="other" otherclass="datatype">length</refmiscinfo>
-</refmeta>
-<refnamediv>
-<refname>column.gap.back</refname>
-<refpurpose>Gap between columns in back matter</refpurpose>
-</refnamediv>
-
-<refsynopsisdiv>
-<src:fragment xml:id="column.gap.back.frag">
-<xsl:param name="column.gap.back">12pt</xsl:param>
-</src:fragment>
-</refsynopsisdiv>
-
-<refsection><info><title>Description</title></info>
-
-<para>Specifies the gap between columns in back matter (if
-<parameter>column.count.back</parameter> is greater than one).</para>
-
-</refsection>
-</refentry>