For advanced git commands training

You can make any training in test branch

## git reset
To make a commit you need to do 3 steps:
1. Make changes
2. Add them to staging area
3. Make a commit

```
git reset --soft      # resets #3 only
git reset (--mixed)   # resets #3 and #2
git reset --hard      # resets all #3, #2 and #1
```
## git rebase
```
git rebase <hash>     # rebase using commits's hash
git rebase -i HEAD~n  # interactive rebase for last n commits 
```