GRIDMATRIX: default char set is GB 2312 only, not Latin-1 with GB 2312 alt

HANXIN/QRCODE: use Hanzi/Kanji modes when compatible ECIs given
manual: one true source now manual.pmd from which manual.txt is generated
CLI: man page moved from frontend/zint.1.gz to docs/zint.1.gz, now
  generated from docs/zint.1.pmd
add README.linux to root dir

docs/inc_before_body_pdf.tex

@@ -0,0 +1,15 @@
+\begin{center}
+\end{center}
+\begin{figure}
+\begin{center}
+\includegraphics{images/zint.png}
+\vfill
+\includegraphics{images/zint-qt.png}
+\end{center}
+\end{figure}
+\hypersetup{
+  pdfauthor=Robin Stuart,
+  pdfsubject={Zint},
+  pdfkeywords={zint,barcode,generator}
+}
+\thispagestyle{empty}