Implement pagination for multicast introspect output

[Nischal Sheth]

Implement pagination for multicast introspect output.
Should return a fixed number of entries per page.
Should not examine an unlimited number of multicast tables in one
Task run when a filter is specified.

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/13065
Submitter: Nischal Sheth (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/13090
Submitter: Nischal Sheth (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Reviewed: https://review.opencontrail.org/13065
Committed: http://github.org/Juniper/contrail-controller/commit/fcc0f5cb8954baa032fdeb16ddde88cb1220f492
Submitter: Zuul
Branch: master

commit fcc0f5cb8954baa032fdeb16ddde88cb1220f492
Author: Nischal Sheth <email address hidden>
Date: Thu Aug 13 15:39:51 2015 -0700

Support pagination of output for multicast manager introspect

Limit the maximum number of entries displayed on a single page.
A next_batch link is generated if there are more entries to be
displayed.

Also limit maximum number of entries examined in one invocation of
the callback routine. This comes into play when there is a search
string specified and many entries don't match it. A partial page
is saved in user-allocated data and the next invocation of callback
appends to it. This is repeated till there's a full page or there
are no more entries in the table.

Following changes are implemented:

- Move code from bgp_sandesh.cc to bgp_show_multicast_manager.cc
- Use class template BgpShowHandler to avoid code duplication
- Implement iteration limit to avoid hogging CPU from introspect
- Reuse type parameterized tests to also cover multicast manager
- Remove older unit test which was limited in scope
- Sprinkle const as required

Change-Id: I190cfbaaa58ac52ce63fb6bd916c040ab100e742
Closes-Bug: 1479428

[OpenContrail Admin (ci-admin-f)]

Reviewed: https://review.opencontrail.org/13090
Committed: http://github.org/Juniper/contrail-controller/commit/f4d00e1dfd4f318bbc027213e12afe366a338f0b
Submitter: Zuul
Branch: R2.20

commit f4d00e1dfd4f318bbc027213e12afe366a338f0b
Author: Nischal Sheth <email address hidden>
Date: Thu Aug 13 15:39:51 2015 -0700

Support pagination of output for multicast manager introspect

Limit the maximum number of entries displayed on a single page.
A next_batch link is generated if there are more entries to be
displayed.

Also limit maximum number of entries examined in one invocation of
the callback routine. This comes into play when there is a search
string specified and many entries don't match it. A partial page
is saved in user-allocated data and the next invocation of callback
appends to it. This is repeated till there's a full page or there
are no more entries in the table.

Following changes are implemented:

- Move code from bgp_sandesh.cc to bgp_show_multicast_manager.cc
- Use class template BgpShowHandler to avoid code duplication
- Implement iteration limit to avoid hogging CPU from introspect
- Reuse type parameterized tests to also cover multicast manager
- Remove older unit test which was limited in scope
- Sprinkle const as required

Change-Id: I190cfbaaa58ac52ce63fb6bd916c040ab100e742
Closes-Bug: 1479428

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/13927
Submitter: Vinay Vithal Mahuli (<email address hidden>)