Adapt to Arduino library 1.5 format compliant

[Naguissa]

1. Repository should be renamed to match library case, STM32Sleep
2. You can add your email and re-check library.properties file.

After that, you can create a release called 1.0.0 (or change version on library.properties) and open an issue requesting inclussion on Arduino library manager here: https://github.com/arduino/Arduino/issues

• Info: https://github.com/arduino/Arduino/wiki/Library-Manager-FAQ