[Vagrant] Associate an existing virtualbox VM with a project
============================================================
Go into the vagrant project directory, then create a file name id in the right
place with ther VM UUID:
```
$ cd <vagrant-project-folder> && \
> echo -n \
> `VBoxManage list vms \
> | grep <vm-short-name> \
> | sed 's/.*{\(.*\)}[^{]*$/\1/'` \
> > .vagrant/machines/<vm-short-name>/virtualbox/id
```
*It directly inject whatever between {} in the result line of the grep to the file without newline*
Check if the change was taken into account
```
$ vagrant status \
> | grep -qE '<vm-short-name>.*not created'
```
*If vagrant status return a line with our <vm-short-name> and "not created"
it means it didn't work, otherwise it's OK*
We can then run vagrant up [<vm-short-name>] to get back our VM
***Note:***
- *If the project only have one VM then <vm-short-name> should be equal to <default>*
- *tested with vagrant 1.8.1 and virtualbox 5.0.20 r106931*
***Sources:***
- [stackoverflow/9434313][1]
[1]: https://stackoverflow.com/questions/9434313/how-do-i-associate-a-vagrant-project-directory-with-an-existing-virtualbox-vm