Append script to a hex file with included filesystem

[microbit-carlos]

If we attempt to append a script to a hex file we should first check if the filesystem is already in use.
If so we should throw an error.

Technically we could move any possible magnetometer calibration data and persistent config page, but this use case is so small it is not worth the effort.

[microbit-carlos]

microbit-fs/src/micropython-appended.ts

Lines 84 to 94 in 9b17c94

	/**
	* Converts the Python code into the Intel Hex format expected by
	* MicroPython and injects it into a Intel Hex string containing a marker.
	*
	* TODO: Throw error if filesystem is using the penultimate page already.
	*
	* @param intelHex - Single string of Intel Hex records to inject the code.
	* @param pyStr - Python code string.
	* @returns Intel Hex string with the Python code injected.
	*/
	function addIntelHexAppendedScript(intelHex: string, pyCode: string): string {