Release 0.14.0

• new devices
  • lis2mdl: add LIS2MDL magnetometer (#187)
  • waveshare: add Waveshare 4.2in B/W e-paper driver (#183)
• enhancements
  • adt7410: add connection test and for that matter connection method
  • gps
    • add speed and heading to fix, as parsed from RMC NMEA sentence
    • improvements and bugfixes (#186)
  • ili9341
    • add support for setting framerate, vsync pause, and reading scanline data.
    • renamed NewSpi() to NewSPI() in accordance with Go naming conventions
  • ws2812
    • add support for ESP8266
    • add support for ESP32
• bugfixes
  • ili9341
    • rix setWindow bug, add CS pin for Clue compatibility. (#180)
    • bugfix for RAMWR bug
  • lis2mdl: turn on read mode on every read, to ensure that magnetometer data is updated
• core
  • i2c
    • switch all i2c drivers definitions to use i2c bus interface type instead of machine package concrete type
    • correct interface definition for I2C Tx function
• testing
  • fix smoke-test unless avr-gcc installed
  • add very basic mock structs for testing i2c devices, based on work done by @rogpeppe
  • improve API surface and implement one more test function in lis2mdl driver
• docs
  • replace README badge for godocs with pkgdocs