PlatformIO Library Manager manifest file

* This library in Web: http://platformio.ikravets.com/#!/lib/show/Energia-RedBot
* Specification: [PlatformIO Library Manager](http://docs.platformio.ikravets.com/en/latest/librarymanager/index.html)
* Integration: [IDE Integration](http://docs.platformio.ikravets.com/en/latest/ide.html)

`library.json` is a library manifest file which can be used with different tools/managers to organise embedded libraries. Currently, only [PlatformIO](http://platformio.ikravets.com) uses it.  How does this look from CLI:

```bash
$ platformio lib search "+energia +redbot"
# Found ... libraries:
# Energia-RedBot        A port of Sparkfun's RedBot Mainboard to BoosterPack form to be used with TI LaunchPads + Energia

$ platformio lib install Energia-RedBot
# Installing Energia-RedBot  library:
# Downloading  [####################################]  100%
# Unpacking  [####################################]  100%
# The library ‘Energia-RedBot' has been successfully installed!

$ platformio lib show Energia-RedBot
# Energia-RedBot
# -------------
# Author: Zack Lalanne
# Keywords: robot, motor, driver
# Version: ***
#
# A port of Sparkfun's RedBot Mainboard to BoosterPack form to be used with TI LaunchPads + Energia

$ platformio lib update
# Updating Energia-RedBot  library:
# Versions: Current=***, Latest=***       [Up-to-date]]
```