libxml2: add an import script

ThirdParty/imported.md

@@ -13,6 +13,7 @@
   * [kwsys](../Utilities/KWSys/update.sh)
   * [libproj](libproj/update.sh)
   * [libharu](libharu/update.sh)
+  * [libxml2](libxml2/update.sh)
   * [lz4](lz4/update.sh)
   * [metaio](../Utilities/MetaIO/update.sh)
   * [mpi4py](mpi4py/update.sh)

ThirdParty/libxml2/update.sh

+#!/usr/bin/env bash
+
+set -e
+set -x
+shopt -s dotglob
+
+readonly name="libxml2"
+readonly ownership="libxml2 Upstream <kwrobot@kitware.com>"
+readonly subtree="ThirdParty/$name/vtk$name"
+readonly repo="https://gitlab.kitware.com/third-party/libxml2.git"
+readonly tag="for/vtk-20181015-2.9.8"
+readonly paths="
+include/libxml/*.h
+include/libxml/xmlversion.h.in
+
+buf.c
+buf.h
+c14n.c
+catalog.c
+chvalid.c
+debugXML.c
+dict.c
+DOCBparser.c
+elfgcchack.h
+enc.h
+encoding.c
+entities.c
+error.c
+globals.c
+hash.c
+HTMLparser.c
+HTMLtree.c
+legacy.c
+libxml.h
+list.c
+parser.c
+parserInternals.c
+pattern.c
+platformTestsC.c
+relaxng.c
+SAX.c
+SAX2.c
+save.h
+schematron.c
+threads.c
+timsort.h
+tree.c
+triodef.h
+trionan.c
+trionan.h
+uri.c
+valid.c
+xinclude.c
+xlink.c
+xmlIO.c
+xmlmemory.c
+xmlmodule.c
+xmlreader.c
+xmlregexp.c
+xmlsave.c
+xmlschemas.c
+xmlschemastypes.c
+xmlstring.c
+xmlunicode.c
+xmlwriter.c
+xpath.c
+xpointer.c
+
+config_cmake.h.in
+.gitattributes
+AUTHORS
+CMakeLists.txt
+Copyright
+libxml2PlatformTests.cmake
+README.kitware.md
+README
+"
+
+extract_source () {
+    git_archive
+}
+
+. "${BASH_SOURCE%/*}/../update-common.sh"