Processing: PeriodicTimer: default constructor with interval = 0

Thus the default constructor initializes a stopped PeriodicTimer.
This should be sane behavior and having a default constructor
makes is easier to create an array of Periodc Timers.
Update LED tables
Whitespace
Update fonts
DynamicArray: implement find() and '>' and '<' operator
enable UART error logger in hardfault handler
parallel_tft: actually implement display rotation setting
Enable hard fault handler by default