Updates the curl examples for apiserver calls.

As the Postgres-operator has been updated to v4.1.0
these examples needed to be updated to work with the
new version. The following changes were made:
- The client version was updated to 4.1.0
- The username/password were updated to use the new
    default values
- removes a backslash from data struct that prevented
    the command from being run without changes

Author: jmckulk

hugo/content/gettingstarted/Design/direct-api-calls.md

@@ -16,7 +16,7 @@ The API server is setup to work with the pgo command line interface so the param
 ###### Get API Server Version
 ```
 curl --cacert $PGO_CA_CERT --key $PGO_CLIENT_KEY --cert $PGO_CA_CERT \
--u username:password -H "Content-Type:application/json" --insecure \
+-u pgoadmin:examplepassword -H "Content-Type:application/json" --insecure \
 -X GET $PGO_APISERVER_URL/version
 ```
 
@@ -25,11 +25,11 @@ You can create a cluster by sending a POST request to `$PGO_APISERVER_URL/cluste
 ###### Create Cluster
 ```
 curl --cacert $PGO_CA_CERT --key $PGO_CLIENT_KEY --cert $PGO_CA_CERT \
--u username:password -H "Content-Type:application/json" --insecure \
--X POST --data '{ \
-  "ClientVersion":"4.0.0", \
-  "Namespace":"pgouser1", \
-  "Name":"mycluster", \
+-u pgoadmin:examplepassword -H "Content-Type:application/json" --insecure \
+-X POST --data \
+  '{"ClientVersion":"4.1.0",
+  "Namespace":"pgouser1",
+  "Name":"mycluster",
   "Series":1}' \
 $PGO_APISERVER_URL/clusters
 ```
@@ -39,21 +39,21 @@ The last two examples show you how to `show` and `delete` a cluster. Notice how
 ###### Show Cluster
 ```
 curl --cacert $PGO_CA_CERT --key $PGO_CLIENT_KEY --cert $PGO_CA_CERT \
--u username:password -H "Content-Type:application/json" --insecure \
--X POST --data '{ \
-  "ClientVersion":"4.0.0", \
-  "Namespace":"pgouser1", \
+-u pgoadmin:examplepassword -H "Content-Type:application/json" --insecure \
+-X POST --data \
+  '{"ClientVersion":"4.1.0",
+  "Namespace":"pgouser1",
   "Clustername":"mycluster"}' \
 $PGO_APISERVER_URL/showclusters
 ```
 
 ###### Delete Cluster
 ```
 curl --cacert $PGO_CA_CERT --key $PGO_CLIENT_KEY --cert $PGO_CA_CERT \
--u username:password -H "Content-Type:application/json" --insecure \
--X POST --data '{ \
-  "ClientVersion":"4.0.0", \
-  "Namespace":"pgouser1", \
+-u pgoadmin:examplepassword -H "Content-Type:application/json" --insecure \
+-X POST --data \
+  '{"ClientVersion":"4.1.0",
+  "Namespace":"pgouser1",
   "Clustername":"mycluster"}' \
 $PGO_APISERVER_URL/clustersdelete
 ```