3.0-mikro-e-cc2520 legacy release

This release contains:

• Basic contiki port on mikro-e platform
• This supports both 6LoWPAN radios viz Ti CC2520 and Cascoda CA8210.
• This is the last release with Ti CC2520 support, for those having old 6LoWPAN clickers since all new ones in the market have Cascoda CA8210 as the default 6LoWPAN radio.

For more details about 6LoWPAN clicker please refer 6LoWPAN clicker Quick Start Guide
For Build instructions, please refer Readme