doc: convert INSTALL-WMAKER into a texinfo source processed by texi2txt

The source of the documentation is in Texinfo format to have the
possibility someday to distribute in more format that just plain text;

The INSTALL-WMAKER original file will now be generated automatically when
running the 'autogen.sh' script (for those who made a git-checkout) and
when running 'make' (for the people who create the distribution archive).

The current document have seen these changes:

 - added all the texinfo header (including the copyright notice);

 - texinfo formatting command in place everywhere applicable;

 - re-ordering of the content to try to get a consistent document.

Apart from this, the document should not have seen any change on the
content, because this deserves dedicated patches to show the evolution.

Signed-off-by: Christophe CURIS <christophe.curis@free.fr>

doc/build/Makefile.am

@@ -1,10 +1,20 @@
 # The list of sources are distributed, but none are to be
 # installed along with Window Maker:
 EXTRA_DIST = Readme \
+	Compilation.texi \
 	Translations.texi
 
 # How to re-generate automatically the top-level text files
-all-local: $(top_srcdir)/README.i18n
+all-local: $(top_srcdir)/INSTALL-WMAKER $(top_srcdir)/README.i18n
+
+$(top_srcdir)/INSTALL-WMAKER: $(srcdir)/Compilation.texi $(top_srcdir)/script/generate-txt-from-texi.sh
+	$(AM_V_GEN)if test ! -e "$(top_srcdir)/INSTALL-WMAKER" -o -w "$(top_srcdir)/INSTALL-WMAKER" ; then \
+	    $(top_srcdir)/script/generate-txt-from-texi.sh \
+	        $(srcdir)/Compilation.texi -o $(top_srcdir)/INSTALL-WMAKER \
+	        -Dversion="$(PACKAGE_VERSION)" -e "$(PACKAGE_BUGREPORT)" ; \
+	else \
+	    echo "Warning: \"$(top_srcdir)/INSTALL-WMAKER\" is not writeable, not regenerated" ; \
+	fi
 
 $(top_srcdir)/README.i18n: $(srcdir)/Translations.texi $(top_srcdir)/script/generate-txt-from-texi.sh
 	$(AM_V_GEN)if test ! -e "$(top_srcdir)/README.i18n" -o -w "$(top_srcdir)/README.i18n" ; then \