[route_check] Move scripts under scripts/ directory, add to setup.py (#489)

Author: jleveque

sonic-utilities-tests/route_check_test.sh scripts/route_check_test.sh

@@ -76,6 +76,8 @@
         'scripts/psushow',
         'scripts/queuestat',
         'scripts/reboot',
+        'scripts/route_check.py',
+        'scripts/route_check_test.sh',
         'scripts/sfpshow',
         'scripts/teamshow',
         'scripts/nbrshow',