Ongoing notifications can only be removed with
termux-notification-remove, which requires the notification id.
An ongoing notification without an id requires a reboot to be removed.
This commit forbids creating such an "unremovable" notification.
... and media options (type, media-{next,previous,pause,play})
Implement these options introduced in termux-api by
termux/termux-api#209 and not yet present in this script.
Fixes https://github.com/termux/termux-api/issues/120
`termux-notification --content '*'` should mean the content of the
notifiation is `*` and not a list of files. The globbing, if desired,
should be done by the shell starting the process
```
echo * # does globbing
echo '*' does not do globbing
termux-notification --content * # Does globbing (but errors, since this
won't be valid syntax).
termux-notification --content '*' # Does globbing without this patch but
shouldn't
```
