Add missing docs to EXTRA_DIST

doc/manual-src/en/Makefile.am

@@ -13,7 +13,8 @@ ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) -c
 
 # Configurations for aria2.
 man_MANS = $(BUILDDIR)/man/aria2c.1
-EXTRA_DIST = $(man_MANS) aria2c.rst index.rst _static/default2.css mkapiref.py
+EXTRA_DIST = $(man_MANS) aria2c.rst libaria2.rst index.rst README.rst\
+	technical-notes.rst _static/default2.css mkapiref.py
 
 $(man_MANS): aria2c.rst
 	$(MAKE) man