Check for qt patched version of wkhtmltopdf for pdf doc generation
diff --git a/Doc/Manual/Makefile b/Doc/Manual/Makefile
index c7769dc..fb5f67c 100644
--- a/Doc/Manual/Makefile
+++ b/Doc/Manual/Makefile
@@ -41,6 +41,7 @@
# 3) <pre> <tt> <code> elements do not always select a fixed-width font - try installing the
# Courier font to fix - these have been added to style.css.
generate: SWIGDocumentation.html
+ wkhtmltopdf --version | grep "with patched qt" || (echo "wkhtmltopdf is not the patched qt version and so cannot be used - download it from http://wkhtmltopdf.org/downloads.html" && false)
wkhtmltopdf --margin-top 20mm --margin-bottom 20mm --margin-left 10mm --margin-right 10mm --header-font-size 6 --footer-font-size 6 --header-spacing 6 --footer-spacing 6 --header-center '[doctitle]' --footer-left '[subsection]' --footer-right '[page]' SWIGDocumentation.html SWIGDocumentation.pdf
SWIGDocumentation.html: swightml.book
