Check our Run Length Encoding can't cause buffer overflows

[peternewman]

Such as here: https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=5539

Confirm, fix if necessary, and add tests for the future for the following usages

• [ ] ESP Net
• [ ] Shownet
• [ ] ola::dmx::RunLengthEncoder
• [ ] USB Pro (change packets?)