Installing Caja Admin from source

Install the dependencies. In Ubuntu and Debian, these are the known dependencies:
- meson
- pluma (optional)
- gettext
- mate-terminal (optional)
- policykit-1
- caja-python

Open a terminal in the project directory and run:

meson -Dprefix=/usr build
cd build
ninja
sudo ninja install

If Caja is running, restart it:
```
caja -q
```
Then start it again.