Lots of changes/additions.
Added:
* Firmware Updater support: Supports the Firmware Updater app (release to follow soon). Enabled by default, can be disabled in the config.
* 3.3V Fix (3V3FIX): Enable if you have stability issues when using 3.3V, works best with VSELECT. Disabled by default, can be enabled in the config.
* `DynamicClockSerial`: Class that extends and modifies HardwareSerial to be compatible with a dynamically changing clock speed. Used through the `ClockedSerial` object/variable.
* `OSCR.cpp` & `OSCR.h`: New files for storing globals. Only contains these new additions for now. More code cleanup to come.
Changed:
* Moved configuration flags to `Config.h` and documented them better.
* Removed `vselect()` function. Now uses `setVoltage()` with the params `VOLTS_SET_3V3` and `VOLTS_SET_5V`.
Known Issues:
* Rarely the LCD backlight turns white when using 3V3FIX. Resetting fixes it. Doesn't affect functionality/usability; it's just weird.
