Example overrides for 'music' api docs (#353)

* Example overrides for 'music' api docs

* Drop 'music' into card page

docs/reference/music/ring-tone.md

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+# @extends
+
+## Example #example
+
+This program checks the speed from the large `A` motor and uses the speed to adjust a tone it rings.
+
+```blocks
+loops.forever(function () {
+    music.ringTone(motors.largeA.speed() * 100)
+})
+```

docs/reference/music/set-volume.md

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+# @extends
+
+## Example #example
+
+Play a tyrannosaurus roar at half volume.
+
+```blocks
+music.setVolume(50)
+music.playSoundEffect(sounds.animalsTRexRoar)
+```

docs/reference/music/stop-all-sounds.md

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+# @extends
+
+## Example #example
+
+Play a sound effect but stop it right away.
+
+```blocks
+music.playSoundEffect(sounds.expressionsCrying)
+music.stopAllSounds()
+```