Fix for Issue 941

Process is to stamp the DB and then make a revision note indicating this is an RCBOPS deployment which is then used to ensure that the DB is NOT stamped on subsequent chef runs.

This commit adds new node attr hash to the ["neutron"]["db"]["stamp"]

The DB stamp will only be attempted when the RCBOPS deployment $REVISION
is not found in the neutron db history.

This also fixes some syntax issues we had in addition to making the recipe more legible.

Issue:
rcbops/chef-cookbooks#941

(cherry picked from commit ddfc0e05eb6f144e26789a3c0ccb111fe9f1b478)
Merge pull request #141 from claco/v4.2.3rc

Merged automatically by jenkins after successful build test
Make api_workers configurable

- Add api_workers attribute and neutron.conf template variable

Issue rcbops/chef-cookbooks#935

(cherry picked from commit c67e4e71588ce31072f2f39a28bca78168b7683a)
Merge pull request #142 from claco/v4.2.3rc

Merged automatically by jenkins after successful build test
Reintroduce l3 router/gateway settings in l3 agent

This partially reverts commits f37dc6e037450a1c6dd0d20e05f99185efa6124f, e969a6f69eefc722c6fcd5d41ddbd6c30d36ce5b

Issue rcbops/chef-cookbooks#933

(cherry picked from commit 571259236b88652a4eef2185c5542b238a652f63)
Merge pull request #143 from claco/v4.2.3rc

Merged automatically by jenkins after successful build test
rpcdaemon: allow specification of enabled plugins

closes rcbops/chef-cookbooks/issues/944

(cherry picked from commit 24297403581e5f1cee61a3c9e402849eee5a1682)
Merge pull request #144 from claco/v4.2.3rc

Merged automatically by jenkins after successful build test