Added resetGlobalParameters().
Minor refactoring of char-processing code. Code that converts a character to upper now uses `toupper()`.
Updated `prog_*` data types to their non-deprecated equivalents.
Macroed out some of the more noisy lines, particularly in relation to PROGMEM.
Minor refactor of `initDevice()`. The portion that sets the global parameters
now sits in a separate function. Hex printing reworked to buffer 4 digits at a
time instead of printing each digit separately.
`printProgString()` updated to be buffered.