Made current contibution rules explicit

Signed-off-by: Nikos Mavrogiannopoulos <nmav@redhat.com>

CONTRIBUTING.md

+# nettle -- Information about our contribution rules
+
+# Test suite:
+
+   New functionality should be accompanied by a test case which verifies
+its correctness, on successful use of the new functionality, as well as on
+failure cases. The nettle test suite is run on "make check".
+
+# Continuous Integration (CI)
+
+We utilize a continuous integration systems, using gitlab-ci.
+
+This is run on a repository mirror at:
+https://gitlab.com/gnutls/nettle
+
+# Sending patches
+
+Please do not utilize the gitlab web interfaces. They are not
+being followed on. Please send your patches to nettle-bugs@lists.lysator.liu.se
+
+

Makefile.in

@@ -220,7 +220,7 @@ DISTFILES = $(SOURCES) $(HEADERS) getopt.h getopt_int.h \
 	libnettle.map.in libhogweed.map.in \
 	config.guess config.sub install-sh texinfo.tex \
 	config.h.in config.m4.in config.make.in	Makefile.in \
-	README AUTHORS COPYING.LESSERv3 COPYINGv2 COPYINGv3 \
+	README CONTRIBUTING.md AUTHORS COPYING.LESSERv3 COPYINGv2 COPYINGv3 \
 	INSTALL NEWS TODO ChangeLog \
 	nettle.pc.in hogweed.pc.in \
 	$(des_headers) descore.README \

README

@@ -42,6 +42,8 @@ Read the manual. Mail me if you have any questions or suggestions.
 You may want to subscribe to the nettle-bugs mailing list. See
 <URL: http://lists.lysator.liu.se/mailman/listinfo/nettle-bugs>.
 
+See CONTRIBUTING.md for information on contibuting patches.
+
 
 Happy hacking,
 /Niels Möller <nisse@lysator.liu.se>