Add changes to add database security to each CouchDB database.   This will
prevent any unauthorized browsing of state data.

Add couchdb methods to expose the CouchDB _security API for PUT and GET to
respectively create and retrieve the database security permissions.

Add the following structure to couchdb to represent the couchdb security
structure:

type DatabaseSecurity struct {
	Admins struct {
		Names []string `json:"names"`
		Roles []string `json:"roles"`
	} `json:"admins"`
	Members struct {
		Names []string `json:"names"`
		Roles []string `json:"roles"`
	} `json:"members"`
}

Add changes to couchdb CreateDatabaseIfNotExist() and apply a security
permission definition based on the configured CouchDB username.  Add the
username to the Admins and Members section.

Change-Id: I8dadd0e1575babef2143c7fb332b863aa0c6be5b
Signed-off-by: Chris Elder <chris.elder@us.ibm.com>