Errors in react-native SDK docs

[CoatedMoose]

Docs in several cases refer to snake_case arguments, but the actual SDK seems to expect camelCase.

In particular, I'm looking at the example code for custom events. The react native instructions refer to custom_data, but inspecting the SDK during development, it seems to expect customData.

A quick skim through the docs, I'm suspicious that there are several other places with similar issue, however, I haven't verified against the code.

[ahmednawar]

Thanks @CoatedMoose for the report! Looping in @aparedes-branch who owns our documentation portal.