Add support to pass and parse config

[PrasadG193]

Add support to pass app details through the config files

Example:

$ kbrew search --config testdata/mysql-config.yaml mysql                                                                                                                       
NAME  VERSION TYPE                                                                                       
mysql 8.3.1   helm                                                                                                                                                                                                 

$ kbrew install --config testdata/mysql-config.yaml mysql --namespace mysql
NAME: mysql                                   
LAST DEPLOYED: Wed Feb 17 09:40:17 2021            
NAMESPACE: mysql                                                                                         
STATUS: deployed                                                                                         
REVISION: 1                                                                                              
TEST SUITE: None                                                                                         
NOTES:                                                                                                   
** Please be patient while the chart is being deployed **
                                                                                                         
Tip:                                                                                                     
                                                    
  Watch the deployment status using the command: kubectl get pods -w --namespace mysql                   
                                                                                                         
Services:                                                                                                
                                                    
  echo Primary: mysql.mysql.svc.cluster.local:3306                                                       
                                                    
Administrator credentials:                                                                               
                                                    
  echo Username: root                                                                                    
  echo Password : $(kubectl get secret --namespace mysql mysql -o jsonpath="{.data.mysql-root-password}" | base64 --decode)
                                                                                                                                                                                                                   
To connect to your database:                     
                                                    
  1. Run a pod that you can use as a client:                                                             
                                                    
      kubectl run mysql-client --rm --tty -i --restart='Never' --image  docker.io/bitnami/mysql:8.0.23-debian-10-r0 --namespace mysql --command -- bash

  2. To connect to primary service (read/write):

      mysql -h mysql.mysql.svc.cluster.local -uroot -p my_database

To upgrade this helm chart:

  1. Obtain the password as described on the 'Administrator credentials' section and set the 'root.password' parameter as shown below:

      ROOT_PASSWORD=$(kubectl get secret --namespace mysql mysql} -o jsonpath="{.data.mysql-root-password}" | base64 --decode)
      helm upgrade mysql bitnami/mysql --set auth.rootPassword=$ROOT_PASSWORD