Copy README into /usr/tests

Add a few sentences describing how to run the tests.

Reviewed by:	ngie
Differential Revision: https://reviews.freebsd.org/D4224

tests/Makefile

@@ -9,6 +9,9 @@ SUBDIR_PARALLEL=
 TESTSDIR= ${TESTSBASE}
 KYUAFILE= yes
 
+FILES+= README
+FILESDIR_README= ${TESTSDIR}
+
 afterinstall: install-tests-local
 install-tests-local: .PHONY
 	${INSTALL_SYMLINK} ../local/tests ${DESTDIR}${TESTSDIR}/local

tests/README

@@ -1,10 +1,19 @@
 src/tests: The FreeBSD test suite
 =================================
 
-This file describes the build infrastructure of the FreeBSD test suite.
-If you are only interested in using the test suite itself, please refer
-to tests(7) instead.
+To run the FreeBSD test suite:
+(1)  Make sure that kyua is installed:
+       pkg install kyua
+(2)  To run the tests:
+       kyua test -k /usr/tests/Kyuafile
+(3)  To see the test results:
+       kyua report  
 
+For further information on using the test suite, read tests(7):
+       man tests
+
+Description of FreeBSD test suite
+=================================
 The build of the test suite is organized in the following manner:
 
 * The build of all test artifacts is protected by the MK_TESTS knob.