Stream definition should be Arduino-compliant

[rgiese]

Problem

The definition of Stream::readBytes is not fully Arduino-compliant: it should accept both a char* and uint8_t* for its buffer pointer. Particle's default compiler settings won't allow the cast to happen automagically, which means some dependent libraries don't compile. Sadness.

Solution

Create a function that accepts the missing type and forwards it with an appropriate cast.

Steps to Test

Build device-os/main with make PLATFORM=argon.

References

Thanks to @DavidEGrayson for recommending this fix on pololu/tic-arduino#1.

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Completeness

• User is totes amazing for contributing!
• Contributor has signed CLA (Info here)
• Problem and Solution clearly stated
• Run unit/integration/application tests on device
• Added documentation
• Added to CHANGELOG.md after merging (add links to docs and issues)

[avtolstoy]

Thanks for the PR. While this does address Stream::readBytes(), if we are making this change, other methods should also be considered e.g. Stream::readBytesUntil(), Stream::find() etc.