Fix generating API docs (Windows makefile).

Also fixes a doxygen warning.

doc/makefile.win32

@@ -7,6 +7,7 @@
 
 RST2HTML=python rst2html.py
 DOXYGEN=doxygen
+CP = copy
 RM = del
 -include ../localwin32.mk
 
@@ -16,6 +17,10 @@ doc: geany.txt
 hacking-doc: ../HACKING
 	$(RST2HTML) -stg --stylesheet=geany.css $^ hacking.html
 
+# FIXME: we should also replace anything like @VERSION@
+Doxyfile: Doxyfile.in
+	$(CP) $< $@
+
 api-doc: Doxyfile
 	$(DOXYGEN)
 

doc/pluginsymbols.c

@@ -32,7 +32,8 @@
  * @link plugindata.h @endlink.
  */
 
-/** Use the PLUGIN_VERSION_CHECK() macro instead. Required by Geany. */
+/** Use the PLUGIN_VERSION_CHECK() macro instead. Required by Geany.
+ * @return . */
 gint plugin_version_check(gint);
 
 /** Use the PLUGIN_SET_INFO() macro to define it. Required by Geany.