[mqtt] initial commit with working mqtt client
[mqtt] add subscription and message callback
[struct] add data structures
[typo] fix typo in title
[dev] open device and optionally set spi speed
[lpd8806] rgb to lpd8806 protocol conversion
[lpd8806] daisy chaining support for even number of columns
[lpd8806] support odd number of columns
[luzz] change index to panel
[gen] add a test frame generator