[SB][Sat] Add satellite information to demo mode docs.

Commands are sent as string extras with key ```command``` (required). Possible values are:

| Command              | Subcommand                 | Argument         | Description

| ---                  | ---                        | ---            | ---

| ---                  |----------------------------|------------------| ---

| ```enter```          |                            |                  | Enters demo mode, bar state allowed to be modified (for convenience, any of the other non-exit commands will automatically flip demo mode on, no need to call this explicitly in practice)

| ```exit```           |                            |                  | Exits demo mode, bars back to their system-driven state

| ```battery```        |                            |                  | Control the battery display

|                      | ```mobile```               |                  | ```show``` to show icon, any other value to hide

|                      |                            | ```datatype```   | Values: ```1x```, ```3g```, ```4g```, ```e```, ```g```, ```h```, ```lte```, ```roam```, any other value to hide

|                      |                            | ```level```      | Sets mobile signal strength level (null or 0-4)

|                      | ```satellite```            |                  | ```show``` to show icon, any other value to hide

|                      |                            | ```connection``` | ```connected```, ```off```, ```on```, or ```unknown``` (matches SatelliteConnectionState enum)

|                      |                            | ```level```      | Sets satellite signal strength level (0-4)

|                      | ```carriernetworkchange``` |                  | Sets mobile signal icon to carrier network change UX when disconnected (```show``` to show icon, any other value to hide)

|                      | ```sims```                 |                  | Sets the number of sims (1-8)

|                      | ```nosim```                |                  | ```show``` to show icon, any other value to hide

```

Show the satellite icon

```

# Sets mobile to be out-of-service, which is required for satellite to show

adb shell am broadcast -a com.android.systemui.demo -e command network -e mobile show -e level 0

# Sets satellite to be connected

adb shell am broadcast -a com.android.systemui.demo -e command network -e satellite show -e level 4 -e connection connected

```

Show the silent volume icon

```