Compilation warning fixes for ESP32 Core 3

Just some changes to avoid compiler warnings.

Added Basic_TX_ESP32 example

3.0.3

Version update

Small tweaks to support compilations and address changes

Centralize address prefix to ease customization

Thanks for the suggestions and improvements!

Closes #73

Scan Channel tweak

Small adjustment to scanChannel allowing the user to set how many measurements are performed. Previously it was 255, now the user can pass in their own value up to 255.

Channel scanning refactor

Breaking change from 2.x:

• printChannel was removed.

Other changes:

• scanChannel was added.
• The ChannelScanner example was refactored to use scanChannel.

Added SplitDataAcrossMultiplePackets example

This is an example to help anyone trying to send a single piece of data that will not fit into a single packet. See #51 for the question that lead to this.

Added SAMD Support

Based on a tip in #50.

Improved two-way communication examples

2.4.2

Removed the need to include esp specific code in printChannels

Improved examples

• Improved the two-way communication examples to help clarify how they work.
• Removed warning when compiling for ATmega microcontrollers.

ESP32 support

Added ESP32 support and example thanks to @bart