update upstream git code example

Example 1: update fork repository

## Add Original Repository
git remote add upstream https://github.com/OriginalOwner/OriginalProject.git

## Verify if Repository is added
git remote -v

## Fetch Updates from Original Repository
git fetch upstream

## Checkout to your master branch
git checkout master

## Get Updates from upstream repo
git merge upstream/master

## Push the commit over 
git push origin master

Example 2: git update upstream url

git remote set-url upstream https://hostname/USERNAME/REPOSITORY.git

Example 3: rebase my fork branch

git checkout master # Make sure you are in master
git remote add author original_repo_that_you_forked_from
    # Note: This is in the format [email protected]:authors_name/repo_name.git
    #       Only needs definition once, future fetches then use it. 
git fetch author
git status # make sure you are in the master branch for the following merge
git merge author/master  # i.e. 'into' your master branch
git checkout your-branch
git rebase master        # Now get those changes into your branch.
git push origin your_branch # You can also use `-f` if necessary and `--all`