Avoid unecessary call to cassandra when using walk.

This commit avoid an unecessary call to cassandra when invoking
the method walk.
According to the documentation cfg.get_range() returns a
tuple of (key, cols).

Change-Id: I4c4c1e62595036e6bea873f7c696f6a1f2a2dfee
set the default DNS port

Change-Id: I7e5d84b8839ce9c509267fddc558b1a53469c9b9
Fix build-id and build-id and build-number displayed as "unknown" on mainline. We now have separate item to report version of agent in contrail-version script. Use the keyword "contrail-vrouter-agent" instead of just "contrail-vrouter" to identify agent.
Change-Id: I2964d0746acf77313af08fad3840fadae4479322
Add a pool of workers for the method walk

This commit adds a pool of workers for the method walk
to increase performance of computing dbe_resync.

Note: a bottleneck has been observed with the client ifmap, it uses
a max concurrency equal to 1. A patch is in progress to increase the
the concurrency.

Benchmarks:
  1000 tenants - client ifmap concurrency = 100

 1   worker:  507 secondes
 10  workers: 52 secondes
 20  workers: 29 secondes
 100 workers: 17 secondes

Co-Authored-By: Edouard Thuleau <edouard.thuleau@cloudwatt.com>
Signed-off-by: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@cloudwatt.com>

Change-Id: Icc2b595cc4ab6d1c25b3a1266ce06205daa642d1
added option to choose ip alloc from start or end, modified gw_ip based on ip alloc option, added check in network_update to reject modified allocation pool, dnsservers and gateway_ip

Conflicts:
	src/config/api-server/vnc_addr_mgmt.py
	src/config/api-server/vnc_cfg_ifmap.py
	src/schema/vnc_cfg.xsd

Change-Id: I35a52e2093d14f8e4815de7d2de9159a5a4afffc
Bring in code for cassandra based discovery server. Do not switch to it yet

Change-Id: I656630492e7e4a5ad07a664905815cb62bfbe3ab
avoid redundant service lookup in subscribe handling

Change-Id: I5d16aebc3d40be14cdac7b73d8dd90dd26d448a2
Initialize hold_time_ in BgpServer.

Change-Id: I7c3c6ff07eb5a192258bc7d8d4f3d00f3772461a
Merge "Avoid unecessary call to cassandra when using walk."
Merge "Bring in code for cassandra based discovery server. Do not switch to it yet"
Merge "avoid redundant service lookup in subscribe handling"
Merge "Initialize hold_time_ in BgpServer."
Merge "added option to choose ip alloc from start or end, modified gw_ip based on ip alloc option, added check in network_update to reject modified allocation pool, dnsservers and gateway_ip"
Add uuid to ACL rule type

Change-Id: I6202c727adb09db0cfdd72d9e6f7f229b62439f1
Merge "Add a pool of workers for the method walk"
Merge "Fix build-id and build-id and build-number displayed as "unknown" on mainline. We now have separate item to report version of agent in contrail-version script. Use the keyword "contrail-vrouter-agent" instead of just "contrail-vrouter" to identify agent. Change-Id: I2964d0746acf77313af08fad3840fadae4479322"
Cleanup SConscript
- Define functions to remove no-exception flags
- Define functions to add test-cases
- Re-org top level agent SConscript to define variables for common and
  test specific libraries
- Disable test cases that fail often
- Split netlink functionality in KSync to different library libksyncnl
- Make modules pkt, services, dns optional

Change-Id: I875fa3de1b45b39f8c0973385dbc1ec6d77d6d55
Merge "Add uuid to ACL rule type"
Merge "Cleanup SConscript - Define functions to remove no-exception flags - Define functions to add test-cases - Re-org top level agent SConscript to define variables for common and   test specific libraries - Disable test cases that fail often - Split netlink functionality in KSync to different library libksyncnl - Make modules pkt, services, dns optional"
Merge "set the default DNS port"