UART Log levels

[liquiddandruff]

As discussed in slack:

there should be a way to set per-task log levels when printing to uart, and have it so by default when code is checked in, all (unimportant) debug output from all tasks are disabled. Instead, the output for these logs can be enabled via the cmd system during runtime.

[richarthurs]

Two print modes:

• FLIGHT will always print the text out (important, non-debug messages)
• DEBUG_ONLY is an additional level of verbosity, prints debug messages for us

Todo:

• add a flag to sfu_uart.c for debug vs. flight print mode. It shall default to flight print mode.
• add #defines to sfu_uart.h for DEBUG_ONLY and FLIGHT print modes. The flag variable will be set to either one of these (flight is default),
• to the following functions, add a parameter for the caller to indicate whether the message will print in flight mode or debug mode
  -- serialSendQ
  -- serialSendQFromISR
  -- serialSendln
• in each of those functions, add appropriate ifs to print the message depending on the debug mode setting. Messages with FLIGHT flag should print in flight mode and debug mode. Messages with DEBUG_ONLY should only print in debug mode.
• Grep through the code and update all calls to those functions to include the FLIGHT flag. We will move anything that is better left as a debug_only level over later.
• add a command to change the log mode. Here's how: https://www.youtube.com/watch?v=hxa5eqtNRWQ