Add proxying healthcheck to consul etc

Add proxying healthcheck to consul etc

Changes are for:
1. Proxying healthcheck API call to Consul's health API using a Nginx
container proxy.  Also some code cleanup.
2. Add support for posting floating addresses to Designate DNS
3. Add addition parameters in heat for supporting spinning up DCAE in
a separate OS/tenant (due to lack of Designate support in main Integration
OS/tenant)

Issue-Id: DCAEGEN2-127
Change-Id: Iac66eddbdd1dfadfc92bf2a1e372c6ad55bd0ab1
Signed-off-by: Lusheng Ji <lji@research.att.com>