Add a skeleton of new ZCL, does not compile!
NON FUNCTIONAL: Added skeleton for determining the length of a read response
NON FUNCTIONAL: Added static function declarations

Fixed some compile errors
Add code to read and write ZCL commands. COMPILES!
Removed old ZCL files
Removed old serial hex code
Add initial ATI support
Fix num_to_hex_chars
Playlist conf file name fixed
Merge branch 'zcl-skeleton' of github:hacklab-jkl/elovalo into zcl-skeleton
Fixed bit shifts and some erronous write code
Send ACK instead of NAK if message has wrong MAC
Fix ATI response to actually include line change
Fix delay issue in serial communication when FPS is low

Fix is done by allowing serial port reading while waiting to reach FPS
limit.
Get rid of unused variable warning with SIMU target
Merge branch 'zcl' into zcl-skeleton
pgmspace.h is moved to common, change include path accordingly
Move non-generated files out of generated/
Merge branch 'zcl' into zcl-skeleton
Make zcl reading functions use a function pointer for reading bytes