specify repositories with changes during backup

[argoyal]

while backing up we need to specify whether some git repositories have tracked/untracked changes. the tool will have to loop through all the repositories with changes. all the changes have to be manually committed in respective git repositories but this application should integrate with GIT cli to provide simple options:

Please note all of this need to be provided with nice CLI tabular prints and colourful messaging.

1. Push all changes to a new branch: When user selects this option, ask user to input a branch name and run necessary git commands to do the backup.
2. Push all changes to current branch: Pushes all the changes to the current git branch.
3. Discard changes and continue: It will disregard any changes and continue.

In all the cases we are not considering the untracked files.

In future we may try to add support for untracked files as well, by improving the simple options.