Remove ksync dependency from other modules like oper
Make init decide on the modules to be used
Cleanup top level SConscript for agent
Change alias to use "agent:" as prefix instead of full path
Group the dependencies for buildinfo to external, common and agent libraries
DHCP Snoop audit must delete only entries not seen from config
Fix bug in kernel scan code in handling DEL_ADDR

Change-Id: I3340561d5847efbefcbbfa151464535c8c8aa5d8
Added scons target test (scons test) which runs most of the unit tests.

Once 'scons test' becomes stable (after a few CI runs), it shall be fully
enforced through CI.

Following unit tests are covered with 'scons test'

controller/src/agent:test
    controller/src/vnsw/agent/cmn:test
    controller/src/vnsw/agent/diag:test
    controller/src/vnsw/agent/init:test
    controller/src/vnsw/agent/kstate:test
    controller/src/vnsw/agent/ksync:test
    controller/src/vnsw/agent/openstack:test
    controller/src/vnsw/agent/oper:test
    controller/src/vnsw/agent/pkt:test
    controller/src/vnsw/agent/services:test
    controller/src/vnsw/agent:test
    controller/src/vnsw/agent/uve:test
    controller/src/vnsw/agent/vgw:test
controller/src/analytics:test
    controller/src/analytics/ruleparser:test
controller/src/base:test
controller/src/bfd:test
controller/src/bgp:test
    controller/src/bgp/enet:test
    controller/src/bgp/evpn:test
    controller/src/bgp/inetmcast:test
    controller/src/bgp/l3vpn:test
    controller/src/bgp/origin-vn:test
    controller/src/bgp/rtarget:test
    controller/src/bgp/tunnel_encap:test
controller/src/control-node:test
controller/src/db:test
controller/src/discovery:test
controller/src/dns:test
controller/src/gendb:test
controller/src/ifmap:test
controller/src/io:test
controller/src/net:test
controller/src/opserver:test
controller/src/query_engine:test
controller/src/schema:test
controller/src/xmpp:test

Below tests have been commented out, as they don't pass [consistently].
Separate bugs shall be raised to fix these.

controller/src/config:test,
syslog_test,
bfd_server_test,
bgp_server_test,
bgp_stress_test,
bgp_xmpp_mcast_test,
rt_network_attr_test,
svc_static_route_intergration_test,
db_test,
db_base_test,
tcp_stress_test,
test_dummy,
test_uve,
xmpp_stream_message_client_test,
xmpp_stream_message_server_test,

Change-Id: Ia5e6c9f409b6182134bc777de40b0385ba2ac176

Comment out a flaky test

Change-Id: If0215a72151f4907089984cbc67aec6659afd871
Remove reference from vmi if last intf static route is deleted

Change-Id: I160123d8f671fe6787f987e08c4c510f70e18096