Design an code system in kotlin, that manage an android client api that meet the requirements belows:
- client can call multiple api by waterfall strategy, if the first api fail, then call the next api to get data.
- can turn off  single api or switch its position in the runtime using firebase remote config.
- disable client, then, it disable all api
- the client should be able to extend more other strategy like call api between 15s each or ignore, etc.. There should be exactly 3 paragraphs separated by the markdown divider: ***.
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