Improvements for Native SDK; rename/restructure for Arduino Library rev. 2.0

• Merged Pull Request #38 -- many thanks to @AEFeinstein !
• Added compatibility with Arduino Library rev. 2.0 and later. This is going to break compatibility with earlier versions, i.e. rev. 1, but since rev. 2.0 was introduced with Arduino IDE 1.5.6 back in 2014 -- this seems safe to do.
  This will close Pull Request #32 -- thanks to @per1234

Clock Stretch Time out fixed

• Fixed #24
• Library tested with ESP8266 Arduino Core 2.4.1

ADT7420 Example moved

• Move ADT7420.ino example into examples/ADT7420 folder to better support in Arduino IDE. Thanks to @per1234 :-)

Added Support to enable or disable Interrupts

• With this release it is possible to enable or disable interrupts during i2c reads and writes, cf. #19
• The readme and wiki has been updated with regards to interrupts
• The wiki contains info on "How to migrate from Wire Library to brzo i2c", cf. #18

Added ACK Polling Support

• Added Support for Acknowledge Polling for EEPROMs, #9
• Removed Floating Point round, #12
• Updated Readme

Added Support for native SDK

• Thanks to @valkuc brzo_i2c can now be compiled with the native SDK, too. see also #9
• Added support to write and receive more bytes #7
• Updated readme

Support longer clock stretch timeouts

• Added support for longer clock stretch timeouts, see #6
• Updated documentation
• added example code for HTU21D