CORD-523 Introduce generic routing service in Segment Routing

Segment Routing now reacts to routes being added/removed through RouteService.

SR will disable SingleSwitchFibInstaller if vRouter is activated

SR will install a routing table entry on
    - The leaf where next hop attaches to
    - The other leaves that points packets to the leaf where next hop attaches to

Host handler no longer add any IP flow for hosts outside the configured subnet
    - We need to explicitly add a per host route via RouteService when needed (vSG)

Change suppressSubnet behavior
    - Before: do not push any flow
    - After: ignore subnet config but still push filtering obj with VLAN 4094
             ARP handler drops all packets from suppressed ports

Additional refactoring
    - Remove vRouterId. Gateway router now needs to be specify through route API
    - Limit the scope of some variables
    - Unify handler.init method name

Change-Id: Idd2fd19fa74e3fa6209eef5cf2ed79957715c5e9
diff --git a/src/main/java/org/onosproject/segmentrouting/AppConfigHandler.java b/src/main/java/org/onosproject/segmentrouting/AppConfigHandler.java
index c24c3ca..34d6776 100644
--- a/src/main/java/org/onosproject/segmentrouting/AppConfigHandler.java
+++ b/src/main/java/org/onosproject/segmentrouting/AppConfigHandler.java
@@ -108,7 +108,7 @@
      *
      * @param deviceId device ID
      */
-    public void initVRouters(DeviceId deviceId) {
+    public void init(DeviceId deviceId) {
         SegmentRoutingAppConfig config =
                 srManager.cfgService.getConfig(srManager.appId, SegmentRoutingAppConfig.class);
         populateVRouter(deviceId, getMacAddresses(config));