GET_CLI 2.0.0

# GET_CLI 2.0.0
Hello, I intend to make some changes to get_cli to release version 2.0.0

## Goals

- [ ] get_cli.yaml
- [ ] Remove nullsafe option

### get_cli.yaml
Get_cli.yaml will be a configuration file for you to easily create your project structure...

### Remove nullsafe option
Now, it's no longer optional to use null safety in Flutter, and this is causing an error in the project creation command.

We will also be looking at the open issues on GitHub to address and fix them.