FIXES: Bug where signup, signin,
edit room and new room screen would fail to open,
because the Flexible Widget cannot be nested in a
Centered Widget.
NOTE: Turns out the widget was not neccessary at all
and rewrote the component's network requests.
showSimpleSnackbar, allows displaying a simple snackbar,
with text and one action button, that can be clicked.
doNetworkRequest is supposed to be a wrapper for the
already existing post* functions.
It aims to make network requests and error handling easier,
by containing all the try&catch blocks
and being able to show snackbars.
If the room was created successfully,
the wizard automatically saves the room data on disk.
This allows it to be cached,
even if the user loses internet connection
right before the wizard exists.
That way the room will be cached.
